3.4.3.5. Reliability model proposed for all EEE families#
This paragraph introduces all the models proposed for the different families. These models are mainly based on the models proposed in FIDES 2022 [NR_EEE_2].
The failure rates calculated with this handbook are given directly in FITs (Failure in Time, corresponding to failures per billion hours). As for the FIDES methodology, these FRs, if corresponding to modelling over several phases constituting a mission profile, are calendar lambdas, as explained in Section 3.4.3.2.1.
Note
For each family, a table presents the different subfamilies. In the “remark” column are the reference linked to the subfamily in the computing tools. This is given as an information for users willing to model with some tool, in order to make sure that they consider the correct model.
3.4.3.5.1. Capacitors (family 01)#
Capacitors are classified as family 01 in EPPL [BR_EEE_9].
All capacitors used for space applications can be modelled through FIDES). The following table presents the different subfamilies and the corresponding models with the FIDES 2022 method.
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The generic formula to be used for all types of capacitors is given in Equations A.2-1 (generic case) and A.2-2 (RF/MW capacitors – see Table 3.4.8).
Note
Type 1 and type 2 correspond to the two types of ceramic capacitors.
Type 1 ceramic capacitors are ceramic capacitors with high stability and low losses compensating the influence of temperature in resonant circuit applications. Their dielectric is paraelectric.
Type 2 corresponds to ceramic capacitors with high volumetric efficiency for buffer, by-pass and coupling applications. Their dielectric is ferroelectric. The FIDES 2022 models differentiate 2 types of type 2: X5R and X7R, with different Thermal Overstress and Csensitivity factors.
3.4.3.5.1.1. Ceramic Capacitors (01 & 02 subfamilies) & Feedthrough (10 subfamily)#
The following table lists the 8 categories that cover the Ceramic Capacitor subfamily based on the CV calculation.
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For the special case of RF/MW capacitors, the choice is given in Table 3.4.8:
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a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration (see Section 3.4.3.2 for details).
b) Calculation of \(\lambda_{\text{Physical}}\)
The formula presenting the $\lambda_{physical}$ for capacitors (ceramic and tantalum) is given in Annex B-1, as Equation B.1-1 with the parameters detailed in Table B.1-1.
Physical stresses for tantalum capacitors (same as for ceramic capacitors)
The physical stresses modelled for capacitors are the thermal, thermal cycling and mechanical factors. The detailed equations are given in Annex B.1, Equations B.1-2, B.1-3 and B.1-4. As the detailed parameters to consider for tantalum capacitors are given in Annex B.1, Table B.1-5.
Induced factor \(\Pi_{\text{induced}}\) (same as for ceramic capacitors):
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{\text{placement}\_ i}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX. Recommendation for the definition of parameter \(\Pi_{\text{placement}\_ i}\):
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(\text{P}_{\text{os}}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) , presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
Ceramic capacitors |
6.05 |
Note
For the 2021 issue of FIDES, the table has been updated, splitting the sensitivity between 5 categories instead of just one (Type I, Type II X5R, Type II X7R, Type II X5R polymer terminations, Type II X7R polymer terminations)
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.11
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\Pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Ceramic capacitors: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: MIL-PRF-xxxx level T, MIL-PRF-xxxx level S, MIL-PRF-xxxx level R, ESCC 300x, NASDA-QTS-xxxx class I (JAXA-QTS-2040E) |
Higher |
3 |
Qualification according to one of the following standards: AEC Q200, MIL-PRF-xxx level P, NASDA-QTS-xxxx class II with identification of manufacturing sites for these standards, qualification according to approved CECC standards. |
Equivalent |
2 |
Qualification according to one of the following MIL-PRF-xxxx level M, or qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much lower |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.
3.4.3.5.1.2. Tantalum Capacitors (03 & 04 families)#
The following table lists the 6 categories that cover the Tantalum Capacitor subfamily
General model for the capacitors family:
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation \(\lambda_{\text{Physical}}\)
Equation
Refer to (3.11.1).
Physical stresses for tantalum capacitors:
Equation
With \(\lambda_{0_{\text{capacitor}}}\), \(E_{a}\), \(S_{\text{reference}}\), \(\gamma_{\text{TCy}}\), \(\gamma_{\text{Mech}}\), \(\gamma_{\text{TH}_{\text{EL}}}\) given in Table XX.
Induced factor \(\Pi_{\text{induced}}\):
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
See Section 3.4.3.5.1.1 for details.
The induced factor \(C_{\text{sensitivity}}\) is provided in the following table:
Note
For the 2021 issue of FIDES, the value has been updated (to 7.43).
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.11
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\Pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.
3.4.3.5.1.3. Plastic Metallized Capacitors (05 family)#
At the time of the FIDES 2009 release, no model existed for plastic films capacitors, but some companies subscribed for the development of such a model which is now included in the FIDES 2021 update.
The following table lists the 5 categories that cover the Plastic Metallized Capacitor subfamily.
<in
General model for the capacitors family:
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation \(\lambda_{\text{Physical}}\)
Physical stresses for plastic film capacitors:
Calculation of \(\Pi_{\text{Film}}\) factor:
For plastic film capacitors: \(\Pi_{\text{Film}}\) factor is calculated from a questionnaire about the environmental conditions which have led to the choice of the plastic film capacitor.
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Induced factor \(\Pi_{\text{induced}}\):
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
See Section 3.4.3.5.1.1 for details.
The induced factor \(C_{\text{sensitivity}}\) is provided in the following table:
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.11
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\Pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Plastic film capacitors: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: AEC Q200, MIL-PRF-xxxx level T, MIL-PRF-xxxx level S, MIL-PRF-xxxx level R, ESCC 400x, NASDA-QTS-xxxx class I (JAXA-QTS-2050D) |
Higher |
3 |
Qualification according to one of the following standards: MIL-PRF-xxx level P, NASDA-QTS-xxxx class II with identification of manufacturing sites for these standards, qualification according to approved CECC standards. |
Equivalent |
2 |
Qualification according to MIL-PRF-xxxx level M, or qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much lower |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.
Summary for the Capacitors family 01
| Section | Component types | Modifications and adaptations for space applications |
|---|---|---|
| 01 | Capacitors |
Addition of the model for plastic film capacitors - FIDES 2021 Modification of the CV product for ceramic capacitors - FIDES 2021 Value of Î Film equal to 1 for all capacitors - FIDES 2021 |
3.4.3.5.2. Connectors (family 02)#
Connectors are classified as family 02 in EPPL [BR_EEE_9].
All connectors used for Space applications can be modelled through FIDES.
The following table presents the different subfamilies and the corresponding models with the FIDES method (in the 2009 version of FIDES but also in the 2021 version for information).
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is the generic formula used in FIDES for connectors:
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item,
\(\Pi_{\text{LF}}\) the factor representing the process to become lead-free if it has to be considered for Space applications, it is equal to 1 (see Section 3.4.3).
All this being based on a mission profile to be defined for the whole unit.
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
With:
\(\lambda_{0_{\text{connector}}}\) : Base failure rate for one group of connector
\(\Pi_{\text{Thermal}}\) : Thermal factor
\(\Pi_{\text{TCy}}\) : Cycling factor
\(\Pi_{\text{Mechanical}}\) : Mechanical factor = 0 for space industry
\(\Pi_{\text{RH}}\) : Humidity factor = 0 for space industry
\(\Pi_{\text{Chemical}}\) : Chemical
\(\Pi_{\text{induced}}\) : Induced factor
Calculation of \(\lambda_{0_{\text{connector}}}\):
Equation
With:
\(\lambda_{\text{Type}}\) equals 0.05 for circular & rectangular connectors, 0.07 for coaxial and 0.1 for PCB connectors.
\(\Pi_{\text{Transfer}}\) depends on the soldering method and is defined by Table 3.4.16.
\(\Pi_{\text{Contact}}\) depends on the number of contacts (\(N_{\text{contact}}\)) of the connector: \(\pi_{\text{contact}} = \left( N_{\text{contact}} \right)^{0.5}\)
\(\Pi_{\text{Cycle}}\) depends on the annual number of cycles (one cycle = one connection + one disconnection): \(\pi_{\text{cycles}} = 0.2 \times \left( N_{annual\_ cycles} \right)^{0.25}\)
Transfer Type |
\(\Pi_{\text{Transfer}}\) |
|
|---|---|---|
Insertion (press fit) |
1 |
ECCO_05 |
Soldered (through) |
6 |
ECCO_06 |
Soldered (SMD) |
10 |
ECCO_07 |
Wrapping (braid) |
3 |
ECCO_08 |
Wrapping (wire) |
2 |
ECCO_09 |
Note
For space applications, where the number of cycles (mating/demating) per year is < 1, \(\Pi_{\text{Cycle}}\) = 0.2.
Physical stresses for connectors:
Equation
Equation
Equation
Equation
Equation
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The value of Pi Placement for connectors is 1.
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
Connectors |
4.40 |
Note
For the 2021 issue of FIDES, the value has been updated (to 3.13).
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.19
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Connectors: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: ESCC 340x level B, NASDA-QTS-xxxx class 1, MIL-DTL-xxxxx, JAXA-QTS-2060E, GSFC |
Higher |
3 |
Qualification according to one of the following standards: Telcordia GR1217-CORE, ARINC 600 and 80x (not space adapted), AECMA, SAE (39029) |
Equivalent |
2 |
Qualification according to one of the following standards: EIA, IEC, SAE, BS |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
Note
In the 2021 issue of FIDES, a table has been added for gauges of circular sections.
Summary for the Connectors family 02
| Section | Component types | Modifications and adaptations for space applications |
|---|---|---|
| 02 |
Value of Î Cycle equal to 0.2 Value of Î Chemical equal to 0.2 |
3.4.3.5.3. Piezo electric devices (family 03)#
Piezo electric devices are classified as family 03 in the EPPL [BR_EEE_9]. Crystal/Quartz resonators/oscillators can be modelled through FIDES.
The following table presents the different subfamilies and the corresponding models with the FIDES method.
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General model for the piezo electric devices family:
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item.
All this being based on a mission profile to be defined for the whole unit.
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
With:
\(\lambda_{0_{\text{piezoelectric}}}\) : Base failure rate for one group of piezoelectric
\(\Pi_{\text{Thermo-electric}}\) : Thermo-electric factor
\(\Pi_{\text{TCy}}\) : Cycling factor
\(\Pi_{\text{Mechanical}}\) : Mechanical factor = 0 for space industry
\(\Pi_{\text{RH}}\) : Humidity factor = 0 for space industry
\(\Pi_{\text{induced}}\) : Induced factor
\(\lambda_{0_{\text{piezoelectric}}}\) corresponds to the basic failure rate defined as follow within the mentioned groups:
Component description |
\(\lambda_{0_{\text{piezoelectric}}}\) |
|
|---|---|---|
Oscillator surface, XO, MCSO case type |
ECPZ_04 |
1.63 |
Oscillator through, XO case type |
ECPZ_03 |
1.60 |
Resonator through, HCxx case type |
ECPZ_01 |
0.82 |
Resonator surface mount |
ECPZ_02 |
0.79 |
Physical stresses for piezo electric devices:
Equation
\(\gamma_{TH - EL}\) depends on the type of piezo electrical devices.
Component description |
\(\gamma_{TH - EL}\) |
|---|---|
Oscillator surface, XO, MCSO case type |
0.31 |
Oscillator through, XO case type |
0.32 |
Resonator through, HCxx case type |
0.16 |
Resonator surface mount |
0.16 |
\(\Pi_{rating\_ TH\_ i}\) follows the rule:
\(\Pi_{rating\_ TH\_ i}\) =1 if \(T_{board\_ ref}\) + \(\Delta T\) < \(T_{max\_ manufacturer}\)- 40°C;
\(\Pi_{rating\_ TH\_ i}\) =5 if \(T_{board\_ ref}\) + \(\Delta T\) ≥ \(T_{max\_ manufacturer}\)- 40°C;
\(\Pi_{rating\_ EL\_ i}\) follows the rule:
\(\Pi_{rating\_ EL\_ i}\) =1 for resonators;
\(\Pi_{rating\_ EL\_ i}\) =1 for oscillators if \(I_{output}\) < 0.8·\(I_{max\_ output}\);
\(\Pi_{rating\_ EL\_ i}\) =5 for oscillators if \(I_{output}\) ≥ 0.8·\(I_{max\_ output}\).
All other parameters are issued from the mission profile.
Equation
\(\gamma_{\text{TCy}}\) depends on the type of piezo electrical devices.
Component description |
\(\gamma_{\text{TCy}}\) |
|---|---|
Oscillator surface, XO, MCSO case type |
0.53 |
Oscillator through, XO case type |
0.42 |
Resonator through, HCxx case type |
0.46 |
Resonator surface mount |
0.59 |
All other parameters are issued from the mission profile.
Equation
\(\gamma_{\text{Mech}}\) depends on the type of piezo electrical devices.
Component description |
\(\gamma_{\text{Mech}}\) |
|---|---|
Oscillator surface, XO, MCSO case type |
0.07 |
Oscillator through, XO case type |
0.14 |
Resonator through, HCxx case type |
0.27 |
Resonator surface mount |
0.15 |
All other parameters are issued from the mission profile.
Equation
\(\gamma_{\text{RH}}\) depends on the type of piezo electrical devices.
Component description |
\(\gamma_{\text{RH}}\) |
|---|---|
Oscillator surface, XO, MCSO case type |
0.09 |
Oscillator through, XO case type |
0.12 |
Resonator through, HCxx case type |
0.11 |
Resonator surface mount |
0.10 |
All other parameters are issued from the mission profile.
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
Resonators |
4.55 |
Quartz |
8.10 |
Note
For the 2021 issue of FIDES, the value has been updated (respectively to 3.95 and 7.25).
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.29
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Piezoelectric components: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: AEC Q200 (Resonator) MIL-PRF-38534 class K (oscillator), MIL-PRF-55310 class S (Oscillator), ESCC 3503 (oscillator)/3501 (resonator) or equivalent |
Higher |
3 |
Qualification according to one of the following standards: MIL-PRF-38534 class H, MIL-PRF-55310 class B |
Equivalent |
2 |
Qualification according to one of the following MIL-PRF-xxxx level M |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
Summary for the Crystal resonators family 03
| Section | Component types | Modifications and adaptations for space applications |
|---|---|---|
| 03 | Piezolectric components |
- |
3.4.3.5.4. Diodes (family 04)#
General diodes and HF/RF diodes are classified as family 04 in EPPL [BR_EEE_9].
All diodes used for Space applications can be modelled through FIDES.
The following table presents the different subfamilies and the corresponding models with the FIDES method, giving the pages where it can be found in both versions (2009 & 2021), for information.
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3.4.3.5.4.1. HF RF Diodes (05, 06, 11, 13, 15 & 16 families)#
General model for the general diodes and the HF RF diodes family:
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{ProcessRFHF}}\) the quality and technical control over the development, manufacturing and use process for the RFHF item,
\(\Pi_{\text{LF}}\) the factor representing the process to become lead-free if it has to be considered for Space applications, it is equal to 1 (see Section 3.4.3).
All this being based on a mission profile to be defined for the whole unit.
With process factor \(\Pi_{\text{Process}}\) according to Section 3.4.3.2.1 and HF/RF process factor \(\Pi_{\text{ProcessRFHF}}\) according to Section 3.4.3.2.5.
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
Basic failure rate \(\lambda_{\text{OTH}}\) is provided in the following table for RFHF diodes:
Diode Type |
Subcategory |
\(\lambda_{\text{OTH}}\) |
Remark |
|---|---|---|---|
PIN, Schottky, tunnel, varactor (RFHF) |
Si and SiGe discrete semiconductor circuit HFDI |
0.0120 |
HFDI_01 |
PIN, Schottky, tunnel, varactor (RFHF) |
Si and SiGe discrete semiconductor circuit HFDA |
0.0120 |
HFDA_01 |
Basic failure rates \(\lambda_{\text{OTCyCase}}\), \(\lambda_{\text{OTCySolderjoints}}\) and \(\lambda_{\text{OMech}}\) are provided in the following table for the packages SODxx and TOxx specifically used in space applications:
|
\(\lambda_{\text{OTH}}\) is a fixed value given in another table, depending on the type of components.
Physical stresses for the general diodes and the RF HF diodes family:
Equation
\(E_{a}\) = 0.7eV;
Equation
for signal diodes up to 1A (PIN, Schottky, signal, varactor) and for HF/RF diodes
for all other diodes, \(\Pi_{\text{El}}\) = 1.
Equation
Equation
Equation
All other parameters are issued from the mission profile.
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
Si and Ge RF diodes |
6.30 |
GaAs RF diodes |
7.40 |
Note
For the 2021 issue of FIDES, these values have not been updated, except for the addition of data for GaN diodes (6.9).
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.36
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Diodes: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: AEC Q101, AEC Q102, MIL-PRF-19500 JANS, ESCC 5000, ESCC 5010 level B, NASDA-QTS-xxxx class I, JAXA-QTS Class I (NASDA-QTS-2030) |
Higher |
3 |
Qualification according to one of the following standards: MIL-PRF-19500 JANTX or JANTXV, ESCC 5010 level C, NASDA-QTS-xxxx class II, JAXA-QTS Class II |
Equivalent |
2 |
Qualification according to one of the following standards: MIL-PRF-19500 JAN or qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
3.4.3.5.4.2. Other Diodes (01, 02, 03, 04, 07, 08, 10 families)#
General model for the general diodes family:
Equation
With process factor \(\Pi_{\text{Process}}\) according to Section 3.4.3.2.1.
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
Basic failure rates \(\lambda_{\text{OTCyCase}}\), \(\lambda_{\text{OTCySolderjoints}}\) and \(\lambda_{\text{OMech}}\) are provided in the following table for the packages SODxx and TOxx specifically used in space applications:
|
\(\lambda_{\text{OTH}}\) is a fixed value given in another table, depending on the type of components.
Type |
Groups |
\(\lambda_{\text{OTH}}\) |
|---|---|---|
Power diodes – Protection diodes >3kW |
8b |
1.4980 |
Power diodes – Thyristors, triacs > 3A |
0.1976 |
|
Power diodes – Rectifying diodes >3A |
2b/10 |
0.1574 |
Power diodes – Zener regulation diodes >1.5W |
3b/4b |
0.0954 |
Low power diodes – Protection diodes <3kW |
8a |
0.0210 |
Low power diodes – rectifying diodes >1A, <3A |
2a |
0.0100 |
Low power diodes – Zener regulation diodes <1.5W |
3a/4a |
0.0080 |
Low power diodes – signal diodes <1A |
1 |
0.0044 |
Physical stresses for the general diodes and the RF HF diodes family:
Equation
\(E_{a}\) = 0.7eV;
Equation
for signal diodes up to 1A (PIN, Schottky, signal, varactor) and for HF/RF diodes
for all other diodes, \(\Pi_{\text{El}}\) = 1.
Equation
Equation
Equation
All other parameters are issued from the mission profile.
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
Regular diodes |
5.20 |
Note
For the 2021 issue of FIDES, the value has been updated (to 6.30).
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.42
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Diodes: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: AEC Q101, AEC Q102, MIL-PRF-19500 JANS, ESCC 5000, ESCC 5010 level B, NASDA-QTS-xxxx class I, JAXA-QTS Class I (NASDA-QTS-2030) |
Higher |
3 |
Qualification according to one of the following standards: MIL-PRF-19500 JANTX or JANTXV, ESCC 5010 level C, NASDA-QTS-xxxx class II, JAXA-QTS Class II |
Equivalent |
2 |
Qualification according to one of the following standards: MIL-PRF-19500 JAN or qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
Summary for the Diodes family 04
| Section | Component types | Modifications and adaptations for space applications |
|---|---|---|
| 04 | Diodes |
Consideration of packages SODxx and TOxx only Removal of the humidity stress Î RH |
3.4.3.5.5. Filters (family 05)#
Filters are classified as family 05 in EPPL [BR_EEE_9].
The HF/RF filters used for Space applications can be modelled through FIDES.
The following table presents the different subfamilies and the corresponding models with the FIDES method, giving the pages where it can be found in both versions (2009 & 2021), for information.
|
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General model for the filters family:
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item,
\(\Pi_{\text{ProcessRFHF}}\)
\(\Pi_{\text{LF}}\) the factor representing the process to become lead-free if it has to be considered for Space applications, it is equal to 1 (see Section 3.4.3).
All this being based on a mission profile to be defined for the whole unit.
With process factor \(\Pi_{\text{Process}}\) according to Section 3.4.3.2.1 and RF/HF process factor \(\Pi_{\text{ProcessRFHF}}\) according to Section 3.4.3.2.5. .
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
\(\lambda_{O_{\text{PassiveRFHF}}}\) corresponds to the basic failure rate defined for sub-groups within the mentioned groups:
For attenuator, load (50Ω), filter, power divider (combiner, splitter) and surface acoustic wave filter, the value is equal to 0.5;
For variable attenuator, tuneable filter, circulator, isolator and phase shifter, the value is equal to 1.0.
Physical stresses for the fuses family:
Equation
\(E_{a}\) = 0.15eV;
η is the duty cycle during the phase.
All other parameters are issued from the mission profile.
Equation
\(\gamma_{\text{TCy}}\) depends on the type of filters:
For circulator, isolator, phase shifter, the value is equal to 0.69;
For all other filters, the value is equal to 0.67.
All other parameters are issued from the mission profile.
Equation
All parameters are issued from the mission profile.
Equation
All other parameters are issued from the mission profile.
Description of the component |
\(\lambda_{0\_ PassiveHFRF}\) |
\(\gamma_{TH\_ EL}\) |
\(\gamma_{TCy}\) |
\(\gamma_{Mech}\) |
\(\gamma_{RH}\) |
|---|---|---|---|---|---|
“Fixed passive components for microwaves: Attenuator, load (50 Ohm), filter, power divider (combiner, splitter)” |
0.5 |
0.01 |
0.67 |
0.30 |
0.02 |
“Variable passive components for microwaves: Variable attenuator, tuneable filter” |
1 |
0.01 |
0.67 |
0.30 |
0.02 |
“Passive components with ferrites for microwaves, circulator, isolator, phase shifter” |
1 |
0.01 |
0.69 |
0.30 |
0 |
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
All filters |
2.60 |
Note
For the 2021 issue of FIDES, this value has been updated to 2.40.
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.48
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Filters: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: AEC Q100, MIL-PRF-38535 class V/Y, MIL-PRF-38510 class S, ESCC 90xx, NASDA-QTS-xxxx classe I, NPSL NASA level 1 |
Higher |
3 |
Qualification according to one of the following standards: MIL-PRF-38535 class Q, MIL-PRF-38535 class M, MIL-PRF-38535 class N, MIL-PRF-38510 class B, NASDA-QTSxxxx class II, NPSL NASA levels 2 and 3 |
Equivalent |
2 |
Qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
Summary for the Filters family 06
| Section | Component types | Modifications and adaptations for space applications |
|---|---|---|
| 05 | Filters |
Classification of Irated according to the standards IEC 60127-1 and UL 248-14 Value of Î Chi equal to 0.6 |
3.4.3.5.6. Fuses (family 06)#
Fuses are classified as family 06 in EPPL [BR_EEE_9]. All fuses used for Space applications can be modelled through FIDES.
The following table presents the different subfamilies and the corresponding models with the FIDES method, giving the pages where it can be found in both versions (2009 & 2021), for information.
|
||||||||||||
General model for the fuses family:
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item,
\(\Pi_{\text{LF}}\) the factor representing the process to become lead-free if it has to be considered for Space applications, it is equal to 1 (see Section 3.4.3).
All this being based on a mission profile to be defined for the whole unit.
With process factor \(\Pi_{\text{Process}}\) according to Section 3.4.3.2.1.
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
Basic failure rate \(\lambda_{O_{\text{fuse}}}\) is equal to 0.5 for all fuses.
Physical stresses for the fuses family:
Equation
\(E_{a}\) = 0.15eV;
\(I_{\text{applied}}\) is the current in the fuse during the considered phase
\(I_{\text{rated}}\) is the rated current in the fuse without opening for an ambient temperature of 20°C. This value is equal to:
rated current for fuses following standard IEC 60127-1 [BR_EEE_4]
75% of rated current for fuses following standard UL 248-14 [BR_EEE_24]
Equation
Equation
Equation
All other parameters are issued from the mission profile.
As the chemical stresses are low for space applications, the value \(\Pi_{\text{Chi}}\) should be equal to 0.6.
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
Fuses |
5.80 |
Note
For the 2021 issue of FIDES, this value has been updated to 5.90.
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.53
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Diodes: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: ESCC 4008, MIL-PRF-23419/08/12 or equivalent |
Higher |
3 |
Qualification according to one of the following standards: IEC 60127 or equivalent |
Equivalent |
2 |
Qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
Summary for the Fuses family 06
| Section | Component types | Modifications and adaptations for space applications |
|---|---|---|
| 06 | Fuses |
Classification of Irated according to the standards IEC 60127-1 and UL 248-14 Value of Î Chi equal to 0.6 |
3.4.3.5.7. Inductors (family 07)#
Inductors are classified as family 07 in EPPL [BR_EEE_9].
All inductors used for Space applications can be modelled through FIDES.
The following table presents the different subfamilies and the corresponding models with the FIDES method, giving the pages where it can be found in both versions (2009 & 2021), for information.
|
|||||||||||||||||||||||||||
Note
Core means coil without winding.
General model for the inductors family:
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item,
\(\Pi_{\text{LF}}\) the factor representing the process to become lead-free if it has to be considered for Space applications, it is equal to 1 (see Section 3.4.3).
All this being based on a mission profile to be defined for the whole unit.
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
\(\lambda_{O_{\text{Magnetic}}}\) corresponds to the basic failure rate defined for sub-groups within the mentioned groups:
For low current wirewound inductors, \(\lambda_{O_{\text{Magnetic}}}\)is equal to 0.025;
For high current (or power) wirewound inductors and multi-layer inductors, \(\lambda_{O_{\text{Magnetic}}}\) is equal to 0.05.
Physical stresses for the inductors family:
Equation
\(E_{a}\) = 0.15eV;
\(\gamma_{TH\_ EL}\) depends on the type of inductors:
For low current wirewound inductors, \(\gamma_{TH\_ EL}\) is equal to 0.01;
For high current (or power) wirewound inductors, \(\gamma_{TH\_ EL}\) is equal to 0.09;
For multi-layer inductors, \(\gamma_{TH\_ EL}\) is equal to 0.71.
All other parameters are issued from the mission profile.
Equation
\(\Pi_{\text{Tcy}}\) depends on the type of inductors:
For low current wirewound inductors,\(\Pi_{\text{Tcy}}\) is equal to 0.73;
For high current (or power) wirewound inductors, \(\Pi_{\text{Tcy}}\) is equal to 0.79;
For multi-layer inductors, \(\Pi_{\text{Tcy}}\) is equal to 0.28.
All other parameters are issued from the mission profile
Equation
\(\gamma_{\text{Mech}}\) depends on the type of inductors:
For low current wirewound inductors, \(\gamma_{\text{Mech}}\) is equal to 0.26;
For high current (or power) wirewound inductors, \(\gamma_{\text{Mech}}\) is equal to 0.12;
For multi-layer inductors, \(\gamma_{\text{Mech}}\) is equal to 0.01.
All other parameters are issued from the mission profile.
Description of the component |
\(\lambda_{0\_ \text{mag}}\) |
\(\gamma_{TH\_ EL}\) |
\(\gamma_{TCy}\) |
\(\gamma_{Mech}\) |
\(\Delta Τ \text{(°C)}\) |
|---|---|---|---|---|---|
“Low current wirewound inductor” |
0.025 |
0.01 |
0.73 |
0.26 |
10 |
“High current (or power) wirewound inductor” |
0.05 |
0.09 |
0.79 |
0.12 |
30 |
“Multi-layer inductor” |
0.05 |
0.71 |
0.28 |
0.01 |
10 |
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
Low current wirewound inductors |
4.05 |
High current (or power) wirewound inductors |
8.05 |
Multi-layer inductors |
4.40 |
Note
For the 2021 issue of FIDES, these values have been updated to respectively 4.73, 6.58 and 4.30.
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.59
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Diodes: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: AEC Q200, MIL-STD-981 class S, MIL-PRF-xxx level T, ESCC 320x, NASDA-QTS-xxxx class I |
Higher |
3 |
Qualification according to one of the following standards: MIL-STD-981 class B, MIL-PRF-xxx level M, NASDA-QTS-xxxx class II with identification of manufacturing sites for these standards, qualification according to approved CECC standards. |
Equivalent |
2 |
Qualification according to one of the following MIL-PRF-xxxx level C, or qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
Summary for the Inductors family 06
| Section | Component types | Modifications and adaptations for space applications |
|---|---|---|
| 07 | Inductors |
- |
3.4.3.5.8. Integrated Circuits (Family 08)#
Integrated circuits are classified as family 08 in EPPL [BR_EEE_9].
All integrated circuits used for Space applications can be modelled through FIDES.
The following table presents the different subfamilies and the corresponding models with the FIDES method, giving the pages where it can be found in both versions (2009 & 2021), for information.
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Note *
In the 2021 issue of FIDES, a GaN MMIC model has been included. The detail is provided in 4.4.2.3, as it has not yet been assessed and is just a proposition for the user.
3.4.3.5.8.1. MMIC (95 family)#
General model for the HF/RF ICs:
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item,
\(\Pi_{\text{ProcessHFRF}}\) the quality and technical control over the development, manufacturing and use process for the RFHF item
\(\Pi_{\text{LF}}\) the factor representing the process to become lead-free if it has to be considered for Space applications, it is equal to 1 (see Section 3.4.3).
All this being based on a mission profile to be defined for the whole unit.
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
\(\lambda_{\text{OTH}}\) is a fixed value given in the following table, depending on the type of components.
Type |
Groups |
\(\lambda_{\text{OTH}}\) |
|---|---|---|
Si, Ge Integrated Circuit |
||
Si RF and HF (MOS) analogue circuit (power amplifier) |
0.53 |
|
Si, SiGe Analogue and mixed circuit (MOS, Bipolar, BiCMOS, MOSFET, PHEMT, HBT) including RF and HF |
0.19 |
|
Si, SiGe RF and digital circuit (MOS, bipolar BiCMOS) |
0.04 |
|
GaAs Integrated Circuit |
||
GaAs, RF and HF analogue circuit (power amplifier) |
0.70* |
|
GaAs Analogue and mixed circuit (MOS, Bipolar, BiCMOS, MOSFET, PHEMT, HBT) including RF and HF |
0.19 |
Note *
\(\lambda_{\text{OTH}}\) for Power HF/RF has been updated in the 2021 issue of the FIDES guide to 0.3756.
The basic failure rates \(\lambda_{\text{ORH}}\), \(\lambda_{\text{OTCyCase}}\), \(\lambda_{\text{OTCySolderjoints}}\) and \(\lambda_{\text{Mech}}\) are calculated through two constants a and b considering the type of package and the number of pins. The formula to apply is:
Equation
All packages have been split into the following six categories:
Plastic PTH;
Ceramic PTH;
Plastic SMD with leads;
Plastic SMD without leads;
Ceramic SMD with leads;
Ceramic SMD without leads.
Typical name |
Description |
|---|---|
SDIP |
Skinny Dual In Line Package |
ZIP |
Zig-zag In Line Package |
QIP |
Quadruple In Line Package |
PGA |
Pin grid array |
SIP, SIPP |
Single In Line Package |
Typical name |
Description |
|---|---|
CERDIP, CDIP, sidebraze |
Ceramic dual in line package |
Ceramic pin grid array |
|
PDIP, TO116 |
Plastic dual in line package |
Typical name |
Description |
|---|---|
PQFP |
Plastic quad flatpack, L lead |
SQFP, TQFP, VQFP, LQFP, HLQFP |
Plastic shrink quad flatpack, L lead Plastic thin quad flatpack, L lead |
Power QFP (RQFP, HQFP, PowerQuad, EdQuad…) |
Plastic quad flatpack with heat shink, L lead |
BQFP |
Bumpered quad flatpack, L lead |
BQFPH |
Bumpered quad flatpack with heat spreader, L lead |
PLCC |
Plastic leaded chip carrier, J lead |
SOJ |
Plastic small outlines, J-lead |
SO, SOP, SOL, SOIC, SOW |
Plastic small outlines, L lead |
TSOP I |
Thin small outlines, leads on small edges, L lead |
TSOP II |
Thin small outlines, leads on long edges, L lead |
SSOP, VSOP, QSOP, VSSOP |
Plastic shrink (pitch) small outlines, L lead |
TSSOP, MSOP, µSOP, µMAX, TVSOP |
Thin shrink small outlines, L lead |
HSSOP, HVSSOP, HTSSOP |
Thermally Enhanced SSOP |
ePad, TSSOP, MSOP, SOIC, SSOP, PSOP |
exposed TSSOP/MSOP/SOIC/SSOP |
CGA, LGA |
Column Grid Array |
HSOP |
Heat Sink Enhanced SOP |
Typical name |
Description |
|---|---|
PBGA WLP 0.3mm |
Plastic ball grid array with solder ball pitch = 0.30 mm |
PBGA CSP BT 0.8 et 0.75mm |
Plastic ball grid array with solder ball pitch = 0.8 et 0.75 mm |
PBGA flex 0.8mm |
Plastic ball grid array with solder ball pitch = 0.8 |
PBGA BT 1.00mm |
Plastic ball grid array with solder ball pitch = 1.00 mm |
PBGA 1.27mm |
Plastic ball grid array with solder ball pitch = 1.27 mm |
PBGA 1.5mm |
Plastic ball grid array with solder ball pitch = 1.5 mm |
FPBGA |
Fine pitch BGA |
FCPBGA |
Flip chip plastic BGA |
Power BGA (TBGA, SBGA …) |
Tape BGABGA, PBGA with heat sink, die top down pitch=1.27mm Super BGA, PBGA with heat sink, die top down pitch=1.27mm |
MAPBGA |
Moulded Array Process Ball Grid |
QFN, aQFN, DFN, MLF, LLP, ODFN, WQFN, VQFN, X2QFN |
Quad flat no lead |
SON, USON, VSON, WSON, X2SON |
Small Outline No Lead |
TEPBGA |
Thermally Enhanced Plastic Ball Grid Array |
Other CSP |
Customized leadframe-based CSP |
Other CSP |
Flexible substrate-based CSP |
Other CSP |
Rigid substrate-based CSP |
Other CSP |
Micro CSP |
PSvfBGA |
Package Stackable Very Thin Fine Pitch BGA (pop) |
PSfcCSP |
Package Stackable Flip Chip Chip Scale Package (pop) |
TMV, SV |
Through Mold Via (POP) |
WL-CSP, WLP, WLB, WCSP, DSBGA |
Wafer-level chip scale package |
WLCSP+ |
Protected Wafer Level Chip Scale Package |
WLFO, eWLB |
Wafer Level Fan-Out |
CABGA, LBGA |
ChipArray BGA |
CTBGA TFBGA |
Thin ChipArray BGA |
CVBGA, VFBGA |
Very thin ChipArray BGA |
Typical name |
Description |
|---|---|
CERPACK |
Ceramic Package |
CQFP, Cerquad |
Ceramic quad flatpack |
CI CGA |
Ceramic land GA + interposer, Ceramic column GA |
CCGA, CLGA |
Ceramic Column Grid Array |
Typical name |
Description |
|---|---|
FCBGA |
Flip chip BGA |
CBGA |
Ceramic ball grid array |
J-CLCC |
J-lead Ceramic leaded chip carrier |
CLCC |
Ceramic leadless chip carrier |
For specific or complex packages, the general model for Hybrids and Multi Chip Modules should be used.
For each stress \(\lambda_{\text{ORH}}\), \(\lambda_{\text{OTCyCase}}\), \(\lambda_{\text{OTCySolderjoints}}\) and \(\lambda_{\text{Mech}}\) corresponding to the stress due to humidity, thermal cycling, thermal cycling of solder joints and mechanical stress, the recommendation for the parameters a and b for estimating the reliability of packages is slightly different according to the number of leads of the components.
For components with 0 to 256 leads, the recommendation for the parameters a and b is the following:
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
For components with more than 256 leads, the recommendation for the parameters a and b is the following:
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Note
In the 2021 issue of FIDES, some evolution concerning the inclusing of underfill has been added. Hence, In Note 4 p127 in the Integrated Circuits Section, it is indicated that in case of underfill, \(\lambda_{\text{OTCySolderjoints}}\) and \(\lambda_{\text{Mech}}\) should be divided by 3. This needs to be assessed before being recommended in the frame of this handbook.
Physical stresses for the integrated circuits family, except ASIC components:
Equation
\(E_{a}\) = 0.7eV;
All other parameters are issued from the mission profile.
Equation
Equation
Equation
Equation
All other parameters are issued from the mission profile.
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
Integrated circuits |
6.3 |
Note
For the 2021 issue of FIDES, this value has been updated to 7.75, and for GaN MMICs, the value of 6.9 has been proposed.
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.73
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Integrated circuits, ASICs: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: AEC Q100, MIL-PRF-38535 class V/Y, MIL-PRF-38510 class S, ESCC 90xx, NASDA-QTS-xxxx classe I, NPSL NASA level 1 |
Higher |
3 |
Qualification according to one of the following standards: MIL-PRF-38535 class Q, MIL-PRF-38535 class M, MIL-PRF-38535 class N, MIL-PRF-38510 class B, NASDA-QTSxxxx class II, NPSL NASA levels 2 and 3 |
Equivalent |
2 |
Qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
3.4.3.5.8.2. ASIC (40, 41 and 42 families)#
General model for the ASIC components:
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item,
\(\Pi_{\text{ProcessASIC}}\) the quality and technical control over the development of ASICs, as defined in 0
With process factor \(\Pi_{\text{Process}}\) according to Section 3.4.3.2.1 and ASIC process factor \(\Pi_{\text{ProcessASIC}}\) according to Section 3.4.3.2.6.
All this being based on a mission profile to be defined for the whole unit.
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
\(\lambda_{\text{OTH}}\) is a fixed value given in the following table, depending on the type of components.
A specific value for the basic failure rate \(\lambda_{\text{OTH}}\) is provided for ASICs, depending on the type of components.
|
The basic failure rates \(\lambda_{\text{ORH}}\), \(\lambda_{\text{OTCyCase}}\), \(\lambda_{\text{OTCySolderjoints}}\) and \(\lambda_{\text{Mech}}\) are calculated through two constants a and b considering the type of package and the number of pins. The formula to apply is:
Equation
All packages have been split into the following six categories:
Plastic PTH;
Ceramic PTH;
Plastic SMD with leads;
Plastic SMD without leads;
Ceramic SMD with leads;
Ceramic SMD without leads.
Typical name |
Description |
|---|---|
SDIP |
Skinny Dual In Line Package |
ZIP |
Zig-zag In Line Package |
QIP |
Quadruple In Line Package |
PGA |
Pin grid array |
SIP, SIPP |
Single In Line Package |
Typical name |
Description |
|---|---|
CERDIP, CDIP, sidebraze |
Ceramic dual in line package |
Ceramic pin grid array |
|
PDIP, TO116 |
Plastic dual in line package |
Typical name |
Description |
|---|---|
PQFP |
Plastic quad flatpack, L lead |
SQFP, TQFP, VQFP, LQFP, HLQFP |
Plastic shrink quad flatpack, L lead Plastic thin quad flatpack, L lead |
Power QFP (RQFP, HQFP, PowerQuad, EdQuad…) |
Plastic quad flatpack with heat shink, L lead |
BQFP |
Bumpered quad flatpack, L lead |
BQFPH |
Bumpered quad flatpack with heat spreader, L lead |
PLCC |
Plastic leaded chip carrier, J lead |
SOJ |
Plastic small outlines, J-lead |
SO, SOP, SOL, SOIC, SOW |
Plastic small outlines, L lead |
TSOP I |
Thin small outlines, leads on small edges, L lead |
TSOP II |
Thin small outlines, leads on long edges, L lead |
SSOP, VSOP, QSOP, VSSOP |
Plastic shrink (pitch) small outlines, L lead |
TSSOP, MSOP, µSOP, µMAX, TVSOP |
Thin shrink small outlines, L lead |
HSSOP, HVSSOP, HTSSOP |
Thermally Enhanced SSOP |
ePad, TSSOP, MSOP, SOIC, SSOP, PSOP |
exposed TSSOP/MSOP/SOIC/SSOP |
CGA, LGA |
Column Grid Array |
HSOP |
Heat Sink Enhanced SOP |
Typical name |
Description |
|---|---|
PBGA WLP 0.3mm |
Plastic ball grid array with solder ball pitch = 0.30 mm |
PBGA CSP BT 0.8 et 0.75mm |
Plastic ball grid array with solder ball pitch = 0.8 et 0.75 mm |
PBGA flex 0.8mm |
Plastic ball grid array with solder ball pitch = 0.8 |
PBGA BT 1.00mm |
Plastic ball grid array with solder ball pitch = 1.00 mm |
PBGA 1.27mm |
Plastic ball grid array with solder ball pitch = 1.27 mm |
PBGA 1.5mm |
Plastic ball grid array with solder ball pitch = 1.5 mm |
FPBGA |
Fine pitch BGA |
FCPBGA |
Flip chip plastic BGA |
Power BGA (TBGA, SBGA …) |
Tape BGA, PBGA with heat sink, die top down pitch=1.27mm Super BGA, PBGA with heat sink, die top down pitch=1.27mm |
MAPBGA |
Moulded Array Process Ball Grid |
QFN, aQFN, DFN, MLF, LLP, ODFN, WQFN, VQFN, X2QFN |
Quad flat no lead |
SON, USON, VSON, WSON, X2SON |
Small Outline No Lead |
TEPBGA |
Thermally Enhanced Plastic Ball Grid Array |
Other CSP |
Customized leadframe-based CSP |
Other CSP |
Flexible substrate-based CSP |
Other CSP |
Rigid substrate-based CSP |
Other CSP |
Micro CSP |
PSvfBGA |
Package Stackable Very Thin Fine Pitch BGA (pop) |
PSfcCSP |
Package Stackable Flip Chip Chip Scale Package (pop) |
TMV, SV |
Through Mold Via (POP) |
WL-CSP, WLP, WLB, WCSP, DSBGA |
Wafer-level chip scale package |
WLCSP+ |
Protected Wafer Level Chip Scale Package |
WLFO, eWLB |
Wafer Level Fan-Out |
CABGA, LBGA |
ChipArray BGA |
CTBGA TFBGA |
Thin ChipArray BGA |
CVBGA, VFBGA |
Very thin ChipArray BGA |
Typical name |
Description |
|---|---|
CERPACK |
Ceramic Package |
CQFP, Cerquad |
Ceramic quad flatpack |
CI CGA |
Ceramic land GA + interposer, Ceramic column GA |
CCGA, CLGA |
Ceramic Column Grid Array |
Typical name |
Description |
|---|---|
FCBGA |
Flip chip BGA |
CBGA |
Ceramic ball grid array |
J-CLCC |
J-lead Ceramic leaded chip carrier |
CLCC |
Ceramic leadless chip carrier |
For specific or complex packages, the general model for Hybrids and Multi Chip Modules should be used.
For each stress \(\lambda_{\text{ORH}}\), \(\lambda_{\text{OTCyCase}}\), \(\lambda_{\text{OTCySolderjoints}}\) and \(\lambda_{\text{Mech}}\) corresponding to the stress due to humidity, thermal cycling, thermal cycling of solder joints and mechanical stress, the recommendation for the parameters a and b for estimating the reliability of packages is slightly different according to the number of leads of the components.
For components with 0 to 256 leads, the recommendation for the parameters a and b is the following:
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
For components with more than 256 leads, the recommendation for the parameters a and b is the following:
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Note
In the 2021 issue of FIDES, some evolution concerning the inclusing of underfill has been added. Hence, In Note 4 p127 in the Integrated Circuits section, it is indicated that in case of underfill, \(\lambda_{\text{OTCySolderjoints}}\) and \(\lambda_{\text{Mech}}\) should be divided by 3. This needs to be assessed before being recommended in the frame of this handbook.
Physical stresses for the integrated circuits family, ASIC components:
Equation
\(E_{a}\) = 0.7eV;
All other parameters are issued from the mission profile.
Equation
Equation
Equation
Equation
All other parameters are issued from the mission profile.
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
Integrated circuits |
6.3 |
Note
For the 2021 issue of FIDES, this value has been updated to 7.75.
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.86
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Integrated circuits, ASICs: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: AEC Q100, MIL-PRF-38535 class V/Y, MIL-PRF-38510 class S, ESCC 90xx, NASDA-QTS-xxxx classe I, NPSL NASA level 1 |
Higher |
3 |
Qualification according to one of the following standards: MIL-PRF-38535 class Q, MIL-PRF-38535 class M, MIL-PRF-38535 class N, MIL-PRF-38510 class B, NASDA-QTSxxxx class II, NPSL NASA levels 2 and 3 |
Equivalent |
2 |
Qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
3.4.3.5.8.3. Integrated Circuits (others)#
General model for the integrated circuits family, except ASIC and HF/RF components:
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item,
\(\Pi_{\text{LF}}\) the factor representing the process to become lead-free if it has to be considered. For Space applications, it is equal to 1 (see Section 3.4.3).
With process factor \(\Pi_{\text{Process}}\) according to Section 3.4.3.2.1.
All this being based on a mission profile to be defined for the whole unit.
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
\(\lambda_{\text{OTH}}\) is a fixed value given in the following table, depending on the type of components.
Type |
Groups |
\(\lambda_{\text{OTH}}\) |
|---|---|---|
30 |
0.166 |
|
Analog and Hybrid circuit (MOS, Bipole, BiCMOS) |
50-69/80 |
0.123 |
Microprocessor, Microcontroller, DSP |
10 |
0.075 |
23-24 |
0.060 |
|
SRAM |
20 |
0.055 |
21 |
0.047 |
|
Digital circuit (MOS, Bipole, BiCMOS) |
80 |
0.021 |
The basic failure rate \(\lambda_{\text{OTH}}\) is a fixed value given in the following table, depending on the type of components.
Equation
All packages have been split into the following six categories:
Plastic PTH;
Ceramic PTH;
Plastic SMD with leads;
Plastic SMD without leads;
Ceramic SMD with leads;
Ceramic SMD without leads.
Typical name |
Description |
|---|---|
SDIP |
Skinny Dual In Line Package |
ZIP |
Zig-zag In Line Package |
QIP |
Quadruple In Line Package |
PGA |
Pin grid array |
SIP, SIPP |
Single In Line Package |
Typical name |
Description |
|---|---|
CERDIP, CDIP, sidebraze |
Ceramic dual in line package |
Ceramic pin grid array |
|
PDIP, TO116 |
Plastic dual in line package |
Typical name |
Description |
|---|---|
PQFP |
Plastic quad flatpack, L lead |
SQFP, TQFP, VQFP, LQFP, HLQFP |
Plastic shrink quad flatpack, L lead Plastic thin quad flatpack, L lead |
Power QFP (RQFP, HQFP, PowerQuad, EdQuad…) |
Plastic quad flatpack with heat shink, L lead |
BQFP |
Bumpered quad flatpack, L lead |
BQFPH |
Bumpered quad flatpack with heat spreader, L lead |
PLCC |
Plastic leaded chip carrier, J lead |
SOJ |
Plastic small outlines, J-lead |
SO, SOP, SOL, SOIC, SOW |
Plastic small outlines, L lead |
TSOP I |
Thin small outlines, leads on small edges, L lead |
TSOP II |
Thin small outlines, leads on long edges, L lead |
SSOP, VSOP, QSOP, VSSOP |
Plastic shrink (pitch) small outlines, L lead |
TSSOP, MSOP, µSOP, µMAX, TVSOP |
Thin shrink small outlines, L lead |
HSSOP, HVSSOP, HTSSOP |
Thermally Enhanced SSOP |
ePad, TSSOP, MSOP, SOIC, SSOP, PSOP |
exposed TSSOP/MSOP/SOIC/SSOP |
CGA, LGA |
Column Grid Array |
HSOP |
Heat Sink Enhanced SOP |
Typical name |
Description |
|---|---|
PBGA WLP 0.3mm |
Plastic ball grid array with solder ball pitch = 0.30 mm |
PBGA CSP BT 0.8 et 0.75mm |
Plastic ball grid array with solder ball pitch = 0.8 et 0.75 mm |
PBGA flex 0.8mm |
Plastic ball grid array with solder ball pitch = 0.8 |
PBGA BT 1.00mm |
Plastic ball grid array with solder ball pitch = 1.00 mm |
PBGA 1.27mm |
Plastic ball grid array with solder ball pitch = 1.27 mm |
PBGA 1.5mm |
Plastic ball grid array with solder ball pitch = 1.5 mm |
FPBGA |
Fine pitch BGA |
FCPBGA |
Flip chip plastic BGA |
Power BGA (TBGA, SBGA …) |
Tape BGA, PBGA with heat sink, die top down pitch=1.27mm Super BGA, PBGA with heat sink, die top down pitch=1.27mm |
MAPBGA |
Moulded Array Process Ball Grid |
QFN, aQFN, DFN, MLF, LLP, ODFN, WQFN, VQFN, X2QFN |
Quad flat no lead |
SON, USON, VSON, WSON, X2SON |
Small Outline No Lead |
TEPBGA |
Thermally Enhanced Plastic Ball Grid Array |
Other CSP |
Customized leadframe-based CSP |
Other CSP |
Flexible substrate-based CSP |
Other CSP |
Rigid substrate-based CSP |
Other CSP |
Micro CSP |
PSvfBGA |
Package Stackable Very Thin Fine Pitch BGA (pop) |
PSfcCSP |
Package Stackable Flip Chip Chip Scale Package (pop) |
TMV, SV |
Through Mold Via (POP) |
WL-CSP, WLP, WLB, WCSP, DSBGA |
Wafer-level chip scale package |
WLCSP+ |
Protected Wafer Level Chip Scale Package |
WLFO, eWLB |
Wafer Level Fan-Out |
CABGA, LBGA |
ChipArray BGA |
CTBGA TFBGA |
Thin ChipArray BGA |
CVBGA, VFBGA |
Very thin ChipArray BGA |
Typical name |
Description |
|---|---|
CERPACK |
Ceramic Package |
CQFP, Cerquad |
Ceramic quad flatpack |
CI CGA |
Ceramic land GA + interposer, Ceramic column GA |
CCGA, CLGA |
Ceramic Column Grid Array |
Typical name |
Description |
|---|---|
FCBGA |
Flip chip BGA |
CBGA |
Ceramic ball grid array |
J-CLCC |
J-lead Ceramic leaded chip carrier |
CLCC |
Ceramic leadless chip carrier |
For specific or complex packages, the general model for Hybrids and Multi Chip Modules should be used.
For each stress \(\lambda_{\text{ORH}}\), \(\lambda_{\text{OTCyCase}}\), \(\lambda_{\text{OTCySolderjoints}}\) and \(\lambda_{\text{Mech}}\) corresponding to the stress due to humidity, thermal cycling, thermal cycling of solder joints and mechanical stress, the recommendation for the parameters a and b for estimating the reliability of packages is slightly different according to the number of leads of the components.
For components with 0 to 256 leads, the recommendation for the parameters a and b is the following:
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
For components with more than 256 leads, the recommendation for the parameters a and b is the following:
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Physical stresses for integrated circuits:
Equation
\(E_{a}\) = 0.7eV;
All other parameters are issued from the mission profile.
Equation
Equation
Equation
Equation
All other parameters are issued from the mission profile.
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
Integrated circuits |
6.3 |
Note
For the 2021 issue of FIDES, this value has been updated to 7.75.
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.99
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Integrated circuits, ASICs: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: AEC Q100, MIL-PRF-38535 class V/Y, MIL-PRF-38510 class S, ESCC 90xx, NASDA-QTS-xxxx classe I, NPSL NASA level 1 |
Higher |
3 |
Qualification according to one of the following standards: MIL-PRF-38535 class Q, MIL-PRF-38535 class M, MIL-PRF-38535 class N, MIL-PRF-38510 class B, NASDA-QTSxxxx class II, NPSL NASA levels 2 and 3 |
Equivalent |
2 |
Qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
Summary for the Integrated Circuits family 08
| Section | Component types | Modifications and adaptations for space applications |
|---|---|---|
| 08 | Integrated Circuits |
Merge of the models for integrated circuits and ASIC components Consideration of 6 categories of packages Values of basic failure rates λ0RH, λ0TcyCase, λ0TcySolderjoints and λ0Mech defined according to the 6 categories of packages 2021: Underfill & DSM considerations 2021: GaN MMIC inclusion |
Note
In the 2021 issue of FIDES, new types of packages and associated values have been included; the impact needs to be evaluated.
3.4.3.5.9. Relays (family 09)#
Relays are classified as family 09 in EPPL [BR_EEE_9].
All relays used for Space applications can be modelled through FIDES, directly or indirectly.
The following table presents the different subfamilies and the corresponding models with the FIDES method, giving the pages where it can be found in both versions (2009 & 2021), for information.
|
|||||||||||||||||
General model for the relays family:
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item,
\(\Pi_{\text{LF}}\) the factor representing the process to become lead-free if it has to be considered for Space applications, it is equal to 1 (see Section 3.4.3).
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
\(\lambda_{O_{\text{Relay}}}\) is equal to 1.1.
For space applications, \(\Pi_{\text{Chemical}}\) is equal to 0, \(\Pi_{\text{manoeuvres}}\) is equal to 1.
Physical stresses for the relays family:
Equation
\(E_{a}\) = 0.25eV;
Equation
\(\Pi_{\text{TH\ contact}}\) is equal to:
1 for temperatures \(T_{board\_ ref} + \Delta T \leq 125{^\circ}C\);
\(\Pi_{\text{MEcontact}} \cdot \Pi_{\text{pole}}\) for temperatures higher than 125°C
With \(\Pi_{\text{Pole}}\) depending on the type of relay (for SPST \(\Pi_{\text{Pole}}\)= 1, for DPDT \(\Pi_{\text{Pole}}\)= 3, for 3PDT \(\Pi_{\text{Pole}}\)= 4.25 and for 4PDT \(\Pi_{\text{Pole}}\)= 5.5).
\(\Pi_{\text{ME\ contact}}\) is equal to:
1.5 for gold plated contact;
1.0 for silver plated contact.
\(\Pi_{\text{TH\ breaking}}\) is equal to:
1.8 for a breaking capacity < 2A;
1.2 for a breaking capacity ≥ 2A;
All other parameters are issued from the mission profile.
Equation
\(\Pi_{\text{Pole}}\) depending on the type of relay (for SPST \(\Pi_{\text{Pole}}\)= 1, for DPDT \(\Pi_{\text{Pole}}\)= 3, for 3PDT \(\Pi_{\text{Pole}}\)= 4.25 and for 4PDT \(\Pi_{\text{Pole}}\)= 5.5).
\(\Pi_{\text{EL\ breaking}}\) is equal to:
1.5 for a breaking capacity < 2A;
1.2 for a breaking capacity ≥ 2A;
\(\Pi_{\text{load\ type}}\), \(S_{V}\) and \(S_{I}\) are equal to:
Load type |
\(\Pi_{\text{load\ type}}\) |
\(S_{V}\) |
\(S_{I}\) |
|---|---|---|---|
Resistive |
0.3 |
1 |
\(I_{\text{contact}}/I_{\text{nominal}}\) |
Inductive |
8 |
1 |
\(I_{\text{contact}}/I_{\text{nominal}}\) |
Incandescent lamp |
4 |
\(V_{\text{contact}}/V_{\text{nominal}}\) |
\(I_{\text{contact}}/I_{\text{nominal}}\) |
Capacitive |
6 |
\(V_{\text{contact}}/V_{\text{nominal}}\) |
1 |
\(m_{1}\) and \(m_{2}\) are equal to:
\(V_{\text{contact}}/V_{\text{nominal}}\) |
\(m_{1}\) |
\(I_{\text{contact}}/I_{\text{nominal}}\) |
\(m_{2}\) |
|---|---|---|---|
≤1 |
3 |
≤1 |
3 |
|
8.8 |
|
5.9 |
All other parameters are issued from the mission profile.
Equation
\(\Pi_{\text{prot\ TCY}}\) depends on the relay protection level:
1 for hermetic relays;
3 for sealed or not sealed relays.
All other parameters are issued from the mission profile.
Equation
\(\Pi_{\text{pole}}\)= 4.25 and for 4PDT \(\Pi_{\text{pole}}\)= 5.5).
\(\Pi_{\text{ME\ contact}}\) is equal to:
1.5 for gold plated contact;
1 for silver plated contact.
\(\Pi_{\text{ME\ breaking}}\) is equal to:
3 for a breaking capacity < 2A;
1 for a breaking capacity ≥ 2A.
All other parameters are issued from the mission profile.
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
Relays |
7.55 |
Note
For the 2021 issue of FIDES, this value has been updated to 7.43.
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.106
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Electromechanical relays: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: ESCC 360x, NASDA-QTS-39016A or specific manufacturer specifications based on ESCC |
Higher |
3 |
Qualification according to one of the following standards: MIL-PRF-39016 (or 83536 or 6106) level R, MIL-PRF-39016 (or 83536 or 6106) level P, NASDA-QTS-6106A |
Equivalent |
2 |
Qualification according to one of the following approved EIA, IEC, SAE, BS |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
Summary or the Relays family 09
| Section | Component types | Modifications and adaptations for space applications |
|---|---|---|
|
Addition of the model for bi-stable relays (identical to the model for mono-stable relays) Value of Î Chemical equal to 0 Value of Î manoeuvres equal to 1 Removal of the humidity stress |
3.4.3.5.10. Resistors (family 10)#
Resistors are classified as family 10 in EPPL [BR_EEE_9].
All resistors used for Space applications can be modelled through FIDES.
The following table presents the different subfamilies and the corresponding models with the FIDES method, giving the pages where it can be found in both versions (2009 & 2021), for information.
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Note
HFRF resistors can also be modelled with FIDES, with the HFRF model.
General model for the resistors family:
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item,
\(\Pi_{\text{LF}}\) the factor representing the process to become lead-free if it has to be considered for Space applications, it is equal to 1 (see Section 3.4.3).
With process factor \(\Pi_{\text{Process}}\) according to Section 3.4.3.2.1.
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
\(\lambda_{O_{\text{Resistor}}}\) corresponds to the basic failure rate defined for sub-groups within the mentioned groups:
Groups |
Type of resistor |
\(\lambda_{O_{\text{Resistor}}}\) |
|---|---|---|
1, 8, 9b |
Power film |
0.4 |
2, 3 |
Power wirewound |
0.4 |
1, 8, 9a |
High stability |
from 0.14 to 0.25 in [NR_EEE_2] page 131 |
1, 8, 9c |
Minimelf |
0.1 |
10 |
SMD resistive network |
0.01 \(\sqrt{N_{R}}\) |
With \(N_{R}\) as the number of resistors in the network.
Physical stresses for the resistors family:
Equation
\(E_{a}\) = 0.15eV;
\(\gamma_{TH\_ EL}\) and \(A\) depend on the type of resistors:
Groups |
Type of resistor |
\(A\) |
\(\gamma_{TH\_ EL}\) |
|---|---|---|---|
1, 8, 9b |
Power film |
130 |
0.04 |
2, 3 |
Power wirewound |
130 |
0.01 |
1, 8, 9a |
High stability |
85 |
from 0.07 to 0.18 in [NR_EEE_2] page 131 |
1, 8, 9c |
Minimelf |
85 |
0.04 |
10 |
SMD resistive network |
70 |
0.01 |
All other parameters are issued from the mission profile.
Equation
\(\gamma_{\text{TCy}}\) depends on the type of resistors:
Groups |
Type of resistor |
\(\gamma_{\text{TCy}}\) |
|---|---|---|
1, 8, 9b |
Power film |
0.89 |
2, 3 |
Power wirewound |
0.97 |
1, 8, 9a |
High stability |
from 0.43 to 0.55 in [NR_EEE_2] page 131 |
1, 8, 9c |
Minimelf |
0.89 |
10 |
SMD resistive network |
0.97 |
Equation
\(\gamma_{\text{Mech}}\) depends on the type of resistors:
Groups |
Type of resistor |
\(\gamma_{\text{Mech}}\) |
|---|---|---|
1, 8, 9b |
Power film |
0.01 |
2, 3 |
Power wirewound |
0.01 |
1, 8, 9a |
High stability |
from 0.05 to 0.08 in [NR_EEE_2] page 131 |
1, 8, 9c |
Minimelf |
0.01 |
10 |
SMD resistive network |
0.01 |
All other parameters are issued from the mission profile.
Equation
\(\gamma_{\text{RH}}\) depends on the type of resistors:
Groups |
Type of resistor |
\(\gamma_{\text{RH}}\) |
|---|---|---|
1, 8, 9b |
Power film |
0.06 |
2, 3 |
Power wirewound |
0.01 |
1, 8, 9a |
High stability |
from 0.26 to 0.41 in [NR_EEE_2] page 131 |
1, 8, 9c |
Minimelf |
0.06 |
10 |
SMD resistive network |
0.01 |
All other parameters are issued from the mission profile.
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
Power film |
2.25 |
Power wirewound |
2.25 |
High stability |
5.80 |
Minimelf |
3.85 |
SMD resistive network |
4.25 |
Note
For the 2021 issue of FIDES, these values have been updated, as well the overall denomination of the categories of resistors.
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.116
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Resistors: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: AEC Q200, MIL-PRF-xxxx level T, MIL-PRF-xxxx level S, MIL-PRF-xxxx level R, ESCC 400x, NASDA-QTS-xxxx class I (JAXA-QTS-2050D) |
Higher |
3 |
Qualification according to one of the following standards: MIL-PRF-xxx level P, NASDA-QTS-xxxx class II with identification of manufacturing sites for these standards, qualification according to approved CECC standards. |
Equivalent |
2 |
Qualification according to MIL-PRF-xxxx level M, or qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
Summary for the Resistors family 10
| Section | Component types | Modifications and adaptations for space applications |
|---|---|---|
| 10 | Resistors |
- |
3.4.3.5.11. Thermistors (family 11)#
Thermistors are classified as family 11 in EPPL [BR_EEE_9].
FIDES does not present models for thermistors, hence the models detailed hereafter as based on resistors models. The pages where the models can be found in the two versions of the FIDES guide (2009 & 2021) are provided in the following table.
|
||||||||||||||||||||||
General model for the thermistors family
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item, see Section 3.4.3.2.1,
\(\Pi_{\text{LF}}\) the factor representing the process to become lead-free if it has to be considered for Space applications, it is equal to 1 (see Section 3.4.3).
All this being based on a mission profile to be defined for the whole unit.
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
\(\lambda_{O_{\text{Thermistor}}}\) corresponds to the basic failure rate defined for sub-groups within the mentioned groups:
Groups |
Type of resistor |
\(\lambda_{O_{\text{Thermistor}}}\) |
|---|---|---|
1, 2, 3 |
Low power wirewound |
0.3 |
1, 2, 3 |
High stability |
from 0.14 to 0.25 in FIDES page 131 |
1, 2, 3 |
Minimelf |
0.1 |
Physical stresses for the thermistors family:
Equation
\(E_{a}\) = 0.15eV;
\(\gamma_{TH\_ EL}\) and \(A\) depend on the type of thermistors:
Groups |
Type of resistor |
\(A\) |
\(\gamma_{TH\_ EL}\) |
|---|---|---|---|
1, 2, 3 |
Low power wirewound |
30 |
0.02 |
1, 2, 3 |
High stability |
85 |
from 0.07 to 0.18 in FIDES page 131 |
1, 2, 3 |
Minimelf |
85 |
0.04 |
All other parameters are issued from the mission profile.
Equation
\(\gamma_{\text{TCy}}\) depends on the type of thermistors:
Groups |
Type of resistor |
\(\gamma_{\text{TCy}}\) |
|---|---|---|
1, 2, 3 |
Low power wirewound |
0.96 |
1, 2, 3 |
High stability |
from 0.43 to 0.55 in FIDES p131 |
1, 2, 3 |
Minimelf |
0.89 |
All other parameters are issued from the mission profile.
Equation
\(\gamma_{\text{Mech}}\) depends on the type of thermistors:
Groups |
Type of resistor |
\(\gamma_{\text{Mech}}\) |
|---|---|---|
1, 2, 3 |
Low power wirewound |
0.01 |
1, 2, 3 |
High stability |
from 0.05 to 0.08 in FIDES p131 |
1, 2, 3 |
Minimelf |
0.01 |
All other parameters are issued from the mission profile.
Equation
\(\gamma_{\text{RH}}\) depends on the type of thermistors:
Groups |
Type of resistor |
\(\gamma_{\text{RH}}\) |
|---|---|---|
1, 2, 3 |
Low power wirewound |
0.01 |
1, 2, 3 |
High stability |
from 0.26 to 0.41 in FIDES p131 |
1, 2, 3 |
Minimelf |
0.06 |
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
Low power wirewound |
1.75 |
High stability |
5.80 |
Minimelf |
3.85 |
Note
For the 2021 issue of FIDES, these values have been updated to 1.83, 4.95 and 3.55.
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.116
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Thermistors: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: AEC Q200, MIL-PRF-xxxx level T, MIL-PRF-xxxx level S, MIL-PRF-xxxx level R, ESCC 400x, NASDA-QTS-xxxx class I (JAXA-QTS-2050D) |
Higher |
3 |
Qualification according to one of the following standards: MIL-PRF-xxx level P, NASDA-QTS-xxxx class II with identification of manufacturing sites for these standards, qualification according to approved CECC standards. |
Equivalent |
2 |
Qualification according to MIL-PRF-xxxx level M, or qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
Summary for the Thermistors family 10
| Section | Component types | Modifications and adaptations for space applications |
|---|---|---|
| 11 | Thermistors |
Addition of the model for thermistors |
3.4.3.5.12. Transistors (family 12)#
General transistors and RF HF transistors are classified as family 12 in EPPL [BR_EEE_9].
All transistors used for Space applications can be modelled through FIDES.
The following table presents the different subfamilies and the corresponding models with the FIDES method, giving the pages where it can be found in both versions (2009 & 2021), for information.
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
3.4.3.5.12.1. HF/RF Transistors (10, 11, 13, 14, 15 families)#
General model for the general transistors and the HF/RF transistors family:
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item,
\(\Pi_{\text{ProcessRFHF}}\) the quality and technical control over the development, manufacturing and use process for the RFHF item,
\(\Pi_{\text{LF}}\) the factor representing the process to become lead-free if it has to be considered for Space applications, it is equal to 1 (see Section 3.4.3).
All this being based on a mission profile to be defined for the whole unit.
With process factor \(\Pi_{\text{Process}}\) according to Section 3.4.3.2.1 and HF/RF process factor \(\Pi_{\text{ProcessRFHF}}\) according to Section 3.4.3.2.5.
Note
In the 2021 issue of FIDES, a GaN Transistor model has been included. The detail is provided in XXX, as it has not yet been assessed and is just a proposition for the user.
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
The basic failure rates \(\lambda_{\text{OTCyCase}}\), \(\lambda_{\text{OTCySolderjoints}}\) and \(\lambda_{\text{OMech}}\) are provided in the following table according for the packages SODxx and TOxx specifically used in space applications:
Case |
Equivalent name |
Description |
\(\lambda_{\text{OTCyCase}}\) |
\(\lambda_{\text{OTCySolderjoints}}\) |
\(\lambda_{\text{OMech}}\) |
|---|---|---|---|---|---|
SOD80 |
Mini-MELF, DO213AA |
SMD, Hermetically sealed glass |
0.00781 |
0.03905 |
0.00078 |
SOD87 |
MELF, DO213AB |
SMD, Hermetically sealed glass |
0.00781 |
0.03905 |
0.00078 |
TO18 |
TO71, TO72, SOT31, SOT18 |
Through hole, metal |
0.0101 |
0.0505 |
0.00101 |
TO39 |
SOT5 |
Through hole, metal |
0.0101 |
0.0505 |
0.00101 |
TO52 |
Through hole, metal |
0.0101 |
0.0505 |
0.00101 |
\(\lambda_{\text{OTH}}\) is a fixed value given in another table, depending on the type of components.
Type |
\(\lambda_{\text{OTH}}\) |
|---|---|
Power HF/RF transistor – GaAs > 1W |
0.0927* |
Low power HF/RF transistor – GaAs < 1W |
0.0488* |
Power HF/RF transistor – Silicon Bipolar > 5W |
0.0478 |
Power HF/RF transistor – Silicon MOS > 5W |
0.0202 |
Low power HF/RF transistor – Silicon, Bipolar <5W / SiGe, Bipolar <1W |
0.0138 |
Note *
\(\lambda_{\text{OTH}}\) for Power HF/RF has been updated in the 2021 issue of the FIDES guide to 0.3756.
Physical stresses for the general transistors and the RF HF transistors family:
Equation
\(E_{a}\) = 0.7eV;
Equation
Equation
Equation
All parameters are issued from the mission profile.
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
Si or SiGe RF transistors |
6.30 |
GaAs RF transistors |
7.40 |
Note
For the 2021 issue of FIDES, these values have not been updated.
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.133
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Transistors: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: AEC Q101, AEC Q102, MIL-PRF-19500 JANS, ESCC 5000, ESCC 5010 level B, NASDA-QTS-xxxx class I, JAXA-QTS Class I (NASDA-QTS-2030) |
Higher |
3 |
Qualification according to one of the following standards: MIL-PRF-19500 JANTX or JANTXV, ESCC 5010 level C, NASDA-QTS-xxxx class II, JAXA-QTS Class II |
Equivalent |
2 |
Qualification according to one of the following standards: MIL-PRF-19500 JAN or qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
3.4.3.5.12.2. Transistors (other)#
General model for the general transistors and the transistors family:
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item,
\(\Pi_{\text{LF}}\) the factor representing the process to become lead-free if it has to be considered for Space applications, it is equal to 1 (see Section 3.4.3).
All this being based on a mission profile to be defined for the whole unit.
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
The basic failure rates \(\lambda_{\text{OTCyCase}}\), \(\lambda_{\text{OTCySolderjoints}}\) and \(\lambda_{\text{OMech}}\) are provided in the following table according for the packages SODxx and TOxx specifically used in space applications:
Case |
Equivalent name |
Description |
\(\lambda_{\text{OTCyCase}}\) |
\(\lambda_{\text{OTCySolderjoints}}\) |
\(\lambda_{\text{OMech}}\) |
|---|---|---|---|---|---|
SOD80 |
Mini-MELF, DO213AA |
SMD, Hermetically sealed glass |
0.00781 |
0.03905 |
0.00078 |
SOD87 |
MELF, DO213AB |
SMD, Hermetically sealed glass |
0.00781 |
0.03905 |
0.00078 |
TO18 |
TO71, TO72, SOT31, SOT18 |
Through hole, metal |
0.0101 |
0.0505 |
0.00101 |
TO39 |
SOT5 |
Through hole, metal |
0.0101 |
0.0505 |
0.00101 |
TO52 |
Through hole, metal |
0.0101 |
0.0505 |
0.00101 |
\(\lambda_{\text{OTH}}\) is a fixed value given in another table, depending on the type of components.
Type |
\(\lambda_{\text{OTH}}\) |
|---|---|
Power transistor – Silicon, Bipolar >5W |
0.0478 |
Power transistor – Silicon MOS > 5W |
0.0202 |
Low power transistor – Silicon MOS < 5W |
0.0145 |
Low power transistor – Silicon JFET < 5W |
0.0143 |
Low power transistor – Silicon Bipolar < 5W |
0.0138 |
Physical stresses for the general transistors and the RF HF transistors family:
Equation
\(E_{a}\) = 0.7eV;
Equation
Equation
Equation
All parameters are issued from the mission profile.
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
Regular transistors |
5.20 |
Note
Note: For the 2021 issue of FIDES, this value has been updated to 5.20.
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.139
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Transistors: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: AEC Q101, AEC Q102, MIL-PRF-19500 JANS, ESCC 5000, ESCC 5010 level B, NASDA-QTS-xxxx class I, JAXA-QTS Class I (NASDA-QTS-2030) |
Higher |
3 |
Qualification according to one of the following standards: MIL-PRF-19500 JANTX or JANTXV, ESCC 5010 level C, NASDA-QTS-xxxx class II, JAXA-QTS Class II |
Equivalent |
2 |
Qualification according to one of the following standards: MIL-PRF-19500 JAN or qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
Summary for the Transistors family 12
| Section | Component types | Modifications and adaptations for space applications |
|---|---|---|
| 12 | Transistors |
Consideration of packages SODxx and TOxx only Removal of the humidity stress Î RH |
3.4.3.5.13. Transformers (family 13)#
Transformers are classified as family 13 in EPPL [BR_EEE_9].
All transformers used for Space applications can be modelled through FIDES.
The following table presents the different subfamilies and the corresponding models with the FIDES method, giving the pages where it can be found in both versions (2009 & 2021), for information.
|
|||||||||||||||
General model for the transformers family
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item, see Section 3.4.3.2.1,
\(\Pi_{\text{LF}}\) the factor representing the process to become lead-free if it has to be considered for Space applications, it is equal to 1 (see Section 3.4.3).
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
with:
\(\lambda_{OTH}\) : Base thermal failure rate
\(\Pi_{\text{thermo-electrical}}\) : Thermo-electrical factor
\(\Pi_{\text{TCy}}\) : Cycling factor
\(\Pi_{\text{Mechanical}}\) : Mechanical factor
\(\Pi_{\text{induced}}\) : Induced factor
\(\Pi_{\text{PM}}\) : Part Manufacturing factor
\(\Pi_{\text{P}}\) : Process factor
\(\lambda_{O_{\text{Magnetic}}}\) mentioned groups:
For low power (or low level) transformers (lower than 100W or 100VA), \(\lambda_{O_{\text{Magnetic}}}\) is equal to 0.125;
For high power transformers (equal to or higher than 100W or 100VA), \(\lambda_{O_{\text{Magnetic}}}\) is equal to 0.25.
Physical stresses for the thermistors family:
Equation
\(E_{a}\) = 0.15eV;
\(\gamma_{TH\_ EL}\) depends on the type of transformers:
For low power (or low level) transformers (lower than 100W or 100VA), \(\gamma_{TH\_ EL}\) is equal to 0.01;
For high power transformers (equal to or higher than 100W or 100VA), \(\gamma_{TH\_ EL}\) is equal to 0.15.
All other parameters are issued from the mission profile.
Equation
\(\gamma_{\text{TCy}}\) depends on the type of transformers:
For low power (or low level) transformers (lower than 100W or 100VA), \(\gamma_{\text{TCy}}\) is equal to 0.73;
For high power transformers (equal to or higher than 100W or 100VA), \(\gamma_{\text{TCy}}\) is equal to 0.69.
All other parameters are issued from the mission profile.
Equation
\(\gamma_{\text{Mech}}\) depends on the type of transformers:
For low power (or low level) transformers (lower than 100W or 100VA), \(\gamma_{\text{Mech}}\) is equal to 0.26;
For high power transformers (equal to or higher than 100W or 100VA), \(\gamma_{\text{Mech}}\) is equal to 0.16.
All other parameters are issued from the mission profile.
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
For low power (or low level) transformers (lower than 100W or 100VA) |
6.90 |
For high power transformers (equal to or higher than 100W or 100VA) |
6.80 |
Note
For the 2021 issue of FIDES, these values have been updated to 5.63 and 6.13.
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.144
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Thermistors: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: AEC Q200, MIL-STD-981 class S, MIL-PRF-xxx level T, ESCC 320x, NASDA-QTS-xxxx class I |
Higher |
3 |
Qualification according to one of the following standards: MIL-STD-981 class B, MIL-PRF-xxx level M, NASDA-QTS-xxxx class II with identification of manufacturing sites for these standards, qualification according to approved CECC standards. |
Equivalent |
2 |
Qualification according to one of the following MIL-PRF-xxxx level C, or qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
Summary for the Transformers family 13
| Section | Component types | Modifications and adaptations for space applications |
|---|---|---|
| 13 | Transformers |
Definition of the limit between low power and high power transformers |
3.4.3.5.14. Switches (family 14)#
Switches are classified as family 14 in EPPL [BR_EEE_9].
Most of the switches used for Space applications can be modelled through FIDES.
The following table presents the different subfamilies and the corresponding models with the FIDES method, giving the pages where it can be found in both versions (2009 & 2021), for information.
|
||||||||||||||||||||||||||||||||
General model for the switches family
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item, see Section 3.4.3.2.1,
\(\Pi_{\text{LF}}\) the factor representing the process to become lead-free if it has to be considered for Space applications, it is equal to 1 (see Section 3.4.3).
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
\(\lambda_{O_{\text{Switch}}}\) is equal to 0.85 whatever the switch.
For space applications, \(\Pi_{\text{Chemical}}\) is equal to 0, \(\Pi_{\text{manoeuvres}}\) is equal to 1.
Physical stresses for the switches family:
Equation
\(E_{a}\) = 0.25eV; \(C_{\text{TH}}\) = 1.11;
Equation
\(\Pi_{\text{TH\ contact}}\) is equal to:
1 for temperatures \(T_{board\_ ref} + \mathrm{\Delta}T \leq 125{^\circ}C\);
\(\Pi_{\text{MEcontact}} \cdot \Pi_{\text{pole}}\) for temperatures higher than 125°C;
With \(\Pi_{\text{pole}}\) depending on the type of switch (for SPST \(\Pi_{\text{pole}}\)= 1, for DPDT \(\Pi_{\text{pole}}\)= 3, for 3PDT \(\Pi_{\text{pole}}\)= 4.25 and for 4PDT \(\Pi_{\text{pole}}\)= 5.5).
\(\Pi_{\text{ME\ contact}}\) is equal to:
1.5 for gold plated contact;
1.0 for silver plated contact.
All other parameters are issued from the mission profile.
Equation
\(C_{\text{EL}}\) = 0.56;
\(\Pi_{\text{pole}}\) depending on the type of switch (for SPST \(\Pi_{\text{pole}}\)= 1, for DPDT \(\Pi_{\text{pole}}\)=3, for 3PDT \(\Pi_{\text{pole}}\)=4.25 and for 4PDT \(\Pi_{\text{pole}}\)=5.5).
\(\Pi_{\text{EL\ breaking}}\) is equal to:
1.5 for a breaking capacity < 2A;
1.2 for a breaking capacity ≥ 2A;
\(\Pi_{\text{load\ type}}\), \(S_{V}\) and \(S_{I}\) are equal to:
Load type |
\(\Pi_{\text{load\ type}}\) |
\(S_{V}\) |
\(S_{I}\) |
|---|---|---|---|
Resistive |
0.3 |
1 |
\(I_{\text{contact}}/I_{\text{nominal}}\) |
Inductive |
8 |
1 |
\(I_{\text{contact}}/I_{\text{nominal}}\) |
Incandescent lamp |
4 |
\(V_{\text{contact}}/V_{\text{nominal}}\) |
\(I_{\text{contact}}/I_{\text{nominal}}\) |
Capacitive |
6 |
\(V_{\text{contact}}/V_{\text{nominal}}\) |
1 |
\(m_{1}\) and \(m_{2}\) are equal to:
\(V_{\text{contact}}/V_{\text{nominal}}\) |
\(m_{1}\) |
\(I_{\text{contact}}/I_{\text{nominal}}\) |
\(m_{2}\) |
|---|---|---|---|
≤1 |
3 |
≤1 |
3 |
>1 |
8.8 |
>1 |
5.9 |
All other parameters are issued from the mission profile.
Equation
\(C_{\text{TCy}}\) = 0.56;
\(\Pi_{\text{pole}}\) depends on the type of switch (for SPST \(\Pi_{\text{pole}}\)= 1, for DPDT \(\Pi_{\text{pole}}\)= 3, for 3PDT \(\Pi_{\text{pole}}\)= 4.25 and for 4PDT \(\Pi_{\text{pole}}\)= 5.5).
\(\Pi_{\text{prot\ TCY}}\) depends on the switch protection level:
1 for hermetic switch;
3 for sealed or not sealed switch.
All other parameters are issued from the mission profile.
Equation
\(C_{\text{MECH}}\) = 1.11;
\(\Pi_{\text{pole}}\) depending on the type of switch (for SPST \(\Pi_{\text{pole}}\)= 1, for DPDT \(\Pi_{\text{pole}}\)= 3, for 3PDT \(\Pi_{\text{pole}}\)= 4.25 and for 4PDT \(\Pi_{\text{pole}}\)= 5.5).
\(\Pi_{\text{ME\ contact}}\) is equal to:
1.5 for gold plated contact;
1 for silver plated contact.
\(\Pi_{\text{ME\ breaking}}\) is equal to:
3 for a breaking capacity < 2A;
1 for a breaking capacity ≥ 2A.
All other parameters are issued from the mission profile.
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
Switches |
7.45 |
Note
For the 2021 issue of FIDES, this value has not updated to 7.38.
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.151
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Switches: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: ESCC 370x, MIL-PRF-8805 |
Higher |
3 |
Qualification according to one of the following standards: MIL-PRF-24236, MIL-C-xxxx |
Equivalent |
2 |
Qualification according to one of the following approved EIA, IEC, SAE, BS |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
Summary for the Switches family 14
| Section | Component types | Modifications and adaptations for space applications |
|---|---|---|
| 14 | Switches |
Parameters for “Toggle” switch only Value of ΠChemical equal to 0 Value of Πmanoeuvres equal to 1 Removal of the humidity stress ΠRH |
3.4.3.5.15. Opto-electronics (family 18)#
Opto-electronics are classified as family 18 in EPPL [BR_EEE_9].
Some of the opto-electronics components used for Space applications can be modelled through FIDES.
The following table presents the different subfamilies and the corresponding models with the FIDES method, giving the pages where it can be found in both versions (2009 & 2021), for information.
|
||||||||||||||||||||||||||||||||||||||||||||||||||||
Note
Investigation and assessment according to Section 3.4.4.
3.4.3.5.15.1. LED#
General model for the opto-electronics family:
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item, see Section 3.4.3.2.1,
\(\Pi_{\text{LF}}\) the factor representing the process to become lead-free if it has to be considered for Space applications, it is equal to 1 (see Section 3.4.3).
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
For LEDs, the basic failure rates \(\lambda_{\text{OTH}}\) are fixed values depending on the colour of the LED:
Component description |
\(\lambda_{\text{OTH}}\) |
|---|---|
White colour |
0.05 |
Other colours |
0.01 |
All other basic failure rates \(\lambda_{\text{ORH}}\), \(\lambda_{\text{0TcyCase}}\), \(\lambda_{\text{0TcySolderJoints}}\) and \(\lambda_{\text{0Mech}}\) depend on the maximum direct current, whether the part is feedthrough or SMD, and on the case type as follows:
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Physical stresses for the opto-electronics family:
Equation
\(E_{a}\) = 0.4eV for LEDs. All other parameters are issued from the mission profile.
Equation
Equation
Equation
Equation
All other parameters are issued from the mission profile.
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
LEDs |
4.85 |
Note
For the 2021 issue of FIDES, this value has been updated to 5.68.
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.158
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Optocouplers, LEDs: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: AEC Q101, AEC Q102, MIL-PRF-19500 JANS, ESCC 5000, ESCC 5010 level B, NASDA-QTS-xxxx class I, JAXA-QTS Class I (NASDA-QTS-2030) |
Higher |
3 |
Qualification according to one of the following standards: MIL-PRF-19500 JANTX or JANTXV, ESCC 5010 level C, NASDA-QTS-xxxx class II, JAXA-QTS Class II |
Equivalent |
2 |
Qualification according to one of the following standards: MIL-PRF-19500 JAN or qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
3.4.3.5.15.2. Opto (other)#
General model for the opto-electronics family:
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item, see Section 3.4.3.2.1,
\(\Pi_{\text{LF}}\) the factor representing the process to become lead-free if it has to be considered for Space applications, it is equal to 1 (see Section 3.4.3).
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
For optocouplers, the basic failure rates \(\lambda_{\text{OTH}}\), \(\lambda_{\text{OTCyChip}}\) and \(\lambda_{\text{OCaseMech}}\) are fixed values depending on the type of components:
Component description |
\(\lambda_{\text{OTH}}\) |
\(\lambda_{\text{OTCyChip}}\) |
\(\lambda_{\text{OCaseMech}}\) |
|---|---|---|---|
Optocoupler with photodiode |
0.05 |
0.01 |
0.005 |
Optocoupler with phototransistor |
0.11 |
0.021 |
0.011 |
According to the different types of packages defined in Table 3.4.62 to Table 3.4.67, the basic failure rates \(\lambda_{\text{0TcyCase}}\), \(\lambda_{\text{OTCySolderjoints}}\), \(\lambda_{\text{OCaseMech}}\) and \(\lambda_{\text{ORH}}\) are similar to the basic failure rates of packages of integrated circuits available in Table 3.4.68.
Physical stresses for the opto-electronics family:
Equation
\(E_{a}\) = 0.7eV for optocouplers; All other parameters are issued from the mission profile.
Equation
Equation
Equation
Equation
All other parameters are issued from the mission profile.
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
The induced factor $C_{\text{sensitivity}} is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
Optocouplers |
5.20 |
Note
For the 2021 issue of FIDES, this value has been updated to 5.63.
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.161
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
Optocouplers, LEDs: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: AEC Q101, AEC Q102, MIL-PRF-19500 JANS, ESCC 5000, ESCC 5010 level B, NASDA-QTS-xxxx class I, JAXA-QTS Class I (NASDA-QTS-2030) |
Higher |
3 |
Qualification according to one of the following standards: MIL-PRF-19500 JANTX or JANTXV, ESCC 5010 level C, NASDA-QTS-xxxx class II, JAXA-QTS Class II |
Equivalent |
2 |
Qualification according to one of the following standards: MIL-PRF-19500 JAN or qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
Summary for the Opto-electronics family 18
| Section | Component types | Modifications and adaptations for space applications |
|---|---|---|
| 18 | Optoelectronics |
Merge of the models of optocouplers and LEDs |
3.4.3.5.16. PCB#
PCB are not classified as family in EPPL but as an important part of electronics units modelling, they are considered in this handbook. They are modelled in FIDES as seen in the following table:
|
||||||||||||
General model for the PCB family:
Equation
\(\lambda_{\text{Physical}}\) the physical contribution for each component,
\(\Pi_{\text{PM}}\) the quality and technical control over manufacturing of the item,
\(\Pi_{\text{Process}}\) the quality and technical control over the development, manufacturing and use process for the product containing the item,
\(\Pi_{\text{LF}}\) the factor representing the process to become lead-free if it has to be considered for Space applications, it is equal to 1 (see Section 3.4.3).
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{Physical}}\)
Equation
For space applications, \(\Pi_{\text{Chemical}}\) is equal to 0, \(\Pi_{\text{TV}}\) is equal to 1 because the temperature of the board is always lower than 110°C.
\(\lambda_{\text{OPCB}}\) is issued from the following equation:
Equation
The value \(\Pi_{Techno\_ PCB}\) reflects the effect on reliability prediction of holes and via on the PCB according to this table:
Printed circuit technology identification |
Value of \(\Pi_{Techno\_ PCB}\) |
|---|---|
Through holes |
0.25 |
Blind holes |
0.5 |
Micro-via technology |
1 |
Pad on via technology |
2.5 |
In case of mixing technologies of holes and via on the same PCB, the calculation can be done either:
by considering the value \(\Pi_{Techno\_ PCB}\) as the maximum value of \(\Pi_{Techno\_ PCB}\) corresponding to each different technology,
or by doing a specific calculation of \(\lambda_{\text{OPCB}}\) for each different technology and weighting the results with the area on the PCB of each considered technology.
The value \(\Pi_{\text{Class}}\) reflects the effect on the reliability prediction of the distance between conductors. The table defining this value has been modified with additional values of distance from 800µm to 50µm according to this table:
Minimum conductor width (µm)/ Minimum spacing between conductors or pads (µm) |
Value of \(\Pi_{\text{Class}}\) |
|---|---|
800 / 800 |
1 |
500 / 500 |
1 |
310 / 310 |
2 |
210 / 210 |
3 |
150 / 150 |
4 |
125 / 125 |
5 |
100 / 100 |
6 |
80 / 80 |
7 |
70 / 70 |
8 |
60 / 60 |
9 |
50 / 50 |
10 |
Physical stresses for the PCB family:
Equation
Equation
Equation
All other parameters are issued from the mission profile.
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The Pi Placement depends on the function, there are 6 choices to choose as recalled here from Table XX:
Description of the placement influence |
\(\Pi_{\text{placement}\_ i}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.6 |
Analog low-level non-interface function (<1A) |
1.3 |
Analog low-level interface function (<1A) |
2.0 |
Analog power non-interface function (≥1A) |
1.6 |
Analog power interface function (≥1A) |
2.5 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Technologies |
\(C_{\text{sensitivity}}\) |
|---|---|
PCB |
6.50 |
Note
For the 2021 issue of FIDES, this value has been updated to 5.55.
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in Table 3.4.168
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 with component quality assurance levels \(\text{QA}_{\text{component}}\) defined in the following tables:
PCB: Component quality assurance level |
Position relative to the state of the art |
\(\text{QA}_{\text{component}}\) |
|---|---|---|
Qualification according to one of the following standards: MIL-PRF-31032, MIL-PRF-55110, MIL-PRF-50884, ESCC-Q-ST-70-10, JAXA-QTS-2140 |
Higher |
3 |
Qualification according to following standard: IPC-9701 with identification of manufacturing sites for these standards |
Equivalent |
2 |
Qualification according to one of the following standard: BS CECC 23000, IEC 61189-6 or qualification program internal to the manufacturer and unidentified manufacturing sites |
Lower |
1 |
No information |
Much |
0 |
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
Summary for the PCB family
| Section | Component types | Modifications and adaptations for space applications |
|---|---|---|
| NA | PCB |
Definition of a methodology for mixing technologies of holes and via Consideration of minimum conductor width from 50 to 800µm Value of ΠChemical equal to 0 Value of ΠTV equal to 1 |
3.4.3.5.17. Hybrids (family 40)#
Hybrids are classified as family 40 in EPPL [BR_EEE_9].. They can be modelled with FIDES, as presented in the following table, for FIDES 2009 and 2021.
|
||||||||||||
General model for the Hybrids and Multi Chip Modules family:
Equation
a) Mission profile
In order to model the reliability for each component of a unit, it is necessary to define the mission profile corresponding to the unit under consideration. See Section 3.4.3.1 for details.
b) Calculation of \(\lambda_{\text{element}}\)
For each basic element (microcomponent, wiring, case-substrate, external connections), the general equation is the standard equation:
Equation
with
Equation
For microcomponents associated with bare chips (integrated circuits, transistors or diodes), the failure rate is reduced to:
Equation
\(\lambda_{\text{OTH}}\) and \(\Pi_{\text{Thermique}}\) are corresponding to the basic thermal failure rates as defined in the models corresponding to the type of chip considered, either integrated circuits in Section 3.4.3.5.8 or discrete semiconductors in Section 3.4.3.5.4 and Section 3.4.3.5.12;
The factor \(C_{\text{moulding}}\) is defined as follows for chips:
Type of moulding |
\(C_{\text{moulding}}\) |
|---|---|
Hermetic non-moulded circuit |
1.0 |
Moulded circuit silicon type embedding |
1.4 |
Moulded circuit polyurethane type embedding |
1.6 |
Moulded circuit epoxy type embedding |
2.0 |
The factor \(C_{chip\_ area}\) is defined as follows for chips:
Equation
Type of chip |
\(d\) |
|---|---|
Numeric Si integrated circuits (MOS, Bipolar and BiCMOS) |
0.35 |
Analogue Si integrated circuits (MOS, Bipolar and BiCMOS) |
0.2 |
Discrete circuits |
0.1 |
If the surface of the chip is not known, the following default values are used for the factor \(S\):
Type of chip |
\(S\) (mm²) |
|---|---|
Logical |
75 |
Analogue |
4 |
Weak signal discrete |
0.8 |
Power discrete |
3 |
The factor \(\lambda_{0T\_chip\_TCy}\) is equal to 0.011 for Hybrids and Multi Chip Modules.
Physical stresses for the Hybrids and Multi Chip Modules family:
Equation
The FIDES guide also gives methods to calculate the failure rates for all kind of micro components inside the Multi Chip Modules, such as resistive networks, resistive SMD chips, deposited resistors, capacitors, and multi-layer inductors. It also gives formula for wiring, case, substrate and external connections.
The chemical factor \(\Pi_{\text{Chemical}}\) is calculated for different pollution levels. However, as the Hybrids and Multi Chip Modules are hermetic in space due to the absence of humidity, the chemical factor \(\Pi_{\text{Chemical}}\) is equal to 0.
Induced factor \(\Pi_{\text{induced}}\)
The \(\Pi_{\text{induced}}\) factor allows taking into account the influence of the mission profile as described in Section 3.4.3.1. Its formula is:
Equation
\(\Pi_{placement}\)
The placement factor \(\Pi_{placement}\) and induced factors \(C_{\text{sensitivity}}\) are provided in the following tables:
Placement of the Hybrids / Multi Chip Modules |
\(\Pi_{placement}\) |
|---|---|
Digital non-interface function |
1.0 |
Digital interface function |
1.3 |
Analog low-level non-interface function (<1A) |
1.2 |
Analog low-level interface function (<1A) |
1.5 |
Analog power non-interface function (≥1A) |
1.3 |
Analog power interface function (≥1A) |
1.8 |
\(\Pi_{\text{application}}\)
\(\Pi_{\text{application}}\) represents the influence of the type of application and the environment of the product containing the part. This factor varies depending on the phase of the profile.
It is evaluated through the questions presented in the following table and addressed in Section 3.4.3.2.19:
|
A mark is given for each level: 1 for level 0, 3.2 for level 1 and 10 for level 2. This mark is multiplied by the weight (\(P_{os}\)) and the sum of all the products is divided by 66. For the present application here, we consider \(\Pi_{\text{application}}\) = 1.1, the value determined in the frame of an Airbus Defence & Space observation project, for all in flight phases.
Note
In bold in the table are the levels considered for the space environment (orbit raising and orbit keeping). They represent the typical environment met in space for satellites, hence the figure can be used for all in flight phases for all projects provided they don’t present a specific application; in that case, it has to be re-evaluated.
\(\Pi_{\text{ruggedising}}\)
The ruggedising factor is determined through a 16 questions audit ensuring the evaluation of the procedures established to guarantee the safety and maintenance of the product and that the procedures are indeed applied. See Section 3.4.3.2.17.
\(C_{\text{sensitivity}}\)
The induced factor \(C_{\text{sensitivity}}\) presented in Section 3.4.3.2.21 is provided in the following table:
Type of Hybrids / Multi Chip Modules |
\(C_{\text{sensitivity}}\) |
|---|---|
Metal case, Ceramic case, Ceramic substrate |
5.5 |
Glass-epoxy substrate with moulding |
4.1 |
Glass-epoxy substrate without moulding |
4.8 |
Note
For the 2021 issue of FIDES, these values have not been updated.
c) Component manufacturing factor \(\Pi_{\text{PM}}\)
The Part_Manufacturing factor presented in Section 3.4.3.3 represents the quality of the component. This factor transcribes the confidence that can be attributed to the way the part has been manufactured, through factors quantifying the manufacturing process of the part, the tests ran and the confidence in the manufacturer.
Its high level formula is
Equation
with
These parameters are determined through tables available in FIDES.
\(\text{QA}_{\text{manufacturer}}\) is presented in Section 3.4.3.3.2
\(\text{QA}_{\text{component}}\) is presented in Section 3.4.3.3.3 and defined in the different table in each section dedicated to the components
\(\text{RA}_{\text{component}}\) is presented in Section 3.4.3.3.4
\(\epsilon\)Â is presented in Section 3.4.3.3.7
Component manufacturing factor \(\pi_{\text{PM}}\) according to Section 3.4.3.3 and calculated using the calculation method described to determinate the \(\pi_{\text{PM}}\) of the corresponding components (integrated circuits and discrete semiconductors, resistors, capacitors, inductors).
d) Determination of the \(\Pi_{\text{Process}}\) factor
The \(\Pi_{\text{Process}}\) factor is determined according to the formula presented in Section 3.4.3.2.3.
Summary for Hybrids
| Section | Component types | Modifications and adaptations for space applications |
|---|---|---|
| 40 | Hybrids |
Value of Î Chemical equal to 0 |
3.4.3.5.18. Model of COTS boards for space applications#
COTS board are electronic and off-the-shelf boards generally supplied from specific manufacturers with very little to no information provided on their content. These COTS boards are generally designed to perform a generic or standard functionality such as input / output, memory storage, specific signal data processing or communication protocols. For space applications, they are currently only used for on-ground systems. However, with the development of nanosatellites for “new space”, the request to use these boards is increasing to minimize costs and to reduce development time.
There is presently no existing reliability prediction model for COTS boards adapted to space applications. The methodology proposed in the following is based on the data from manufacturer and especially datasheet and parts list of the boards. In case of no information available from the manufacturers, a possible solution is to perform a reverse engineering of the board and to use the families or part count method to estimate the reliability prediction. This method is clearly not recommended. In fact, only life tests on a sufficiently large amount of COTS boards are suitable to estimate the COTS board reliability when no data are available from the manufacturer.
3.4.3.5.19. Reliability prediction of COTS boards done by manufacturers#
Some manufacturers of COTS boards do provide a reliability prediction for their COTS boards and publish this information inside the datasheet. An assessment of this estimation could be made to appreciate its applicability to space applications. Elements, such as the level of confidence, the methodology applied, number of tested boards, number of failed boards and root cause of failure analysis should be provided by the manufacturers of COTS boards to justify their estimations and to provide rationales of their confidence.
3.4.3.5.20. Reliability prediction of COTS boards with raw data provided by manufacturers#
If the manufacturer agrees to provide a datasheet and a parts list, the best solution is to perform a complete reliability calculation with the methodology provided in this handbook based on this data. This data could provide references of the EEE components, manufacturers of the EEE components, and derating computed by the manufacturer. In the unlikely event that the manufacturers fill the Pi Process questionnaire themselves, the resulting Π~Process~ issued from the questionnaire is used to complete the reliability prediction. If not, as it is difficult to fill in the questionnaire for the manufacturer, an alternate solution is to use a recommended value for Π~Process~ of 4.0 if suppliers of COTS boards have no experience with space applications. In case of manufacturers of COTS boards applying the quality process of space industry and having experience with satellites in orbit, this recommended value can be reduced to 2.5. Consequently, it is difficult to justify a value lower than 2.5 without justified rationales from the COTS boards’ manufacturers.
3.4.3.5.21. Reliability prediction of COTS boards without data provided by manufacturers#
Unfortunately, manufacturers of COTS boards usually do not provide any information. One possible solution to overcome this situation is to identify the EEE components of the board and to reconstruct the parts list by reverse engineering, through visual inspection for instance. As it is not possible to identify all characteristics of the components and to estimate the deratings, a simple and fast calculation based on a families count or part count methods is suggested instead of doing a complete part stress calculation.
The families count prediction method considers all the components without distinguishing the different technologies. The part count prediction method considers all types of components with their various technologies. The method for calculating the reliability prediction of COTS boards with the families count and part count method is provided in Section 3.4.3.5.
If it is not possible to apply the families or part count method due to specific concerns such as boards with potting or boards encapsulated in other systems, a reliability prediction based on calculation is not possible. The alternative is to perform the reliability prediction based on life tests of the COTS boards.
The determination of the number of boards to be tested is done from the χ² law:
Equation
where:
From a fixed failure rate objective \(\lambda\) and with a test with no failure \(n_{f}\)=0, two possible ways to determine the parameters can be followed:
If a fixed number of parts \(n\) is available, the test duration \(t\) is determined from the χ² law; by similarity with other industrial domains and to avoid a too long test duration, a minimum of \(n\)=30 parts is requested for the tests;
If the test duration \(t\) is fixed, the quantity of parts \(n\) to be tested is determined from the χ² law.
For space applications as for other type of applications, the minimum confidence level to use is 60%. With this confidence level, the test duration can last several years or the quantity of parts to test can be huge. So, there is often a compromise to find in order to get an acceptable quantity of parts to test and an acceptable duration of the test.