IEC 61709:2011

Electric components - Reliability - Reference conditions for failure rates and stress models for conversion

IEC 61709:2011 gives guidance on how failure rate data can be employed for reliability prediction of electric components in equipment. Reference conditions are numerical values of stresses that are typically observed by components in the majority of applications. Reference conditions are useful since they are the basis of the calculation of failure rate under any conditions by the application of stress models that take into account the actual operating conditions. This standard also gives guidance on how a database of component failure data can be constructed to provide failure rates that can be used with the included stress models. This edition includes the following significant technical changes with respect to the previous edition:
- the addition of a number of component types and the updating of models for a large number of component types;
- the addition of annexes on reliability prediction, sources of failure rate data and component classification information.

Composants électriques - Fiabilité - Conditions de référence pour les taux de défaillance et modèles de contraintes pour la conversion

La CEI 61709:2011 donne des recommandations concernant les méthodes d'utilisation des données de taux de défaillance pour les prévisions de fiabilité de composants électriques d'équipements. Les conditions de référence sont des valeurs numériques de contraintes généralement observées sur les composants dans la plupart des applications. Ces conditions de référence sont utiles dans la mesure où elles permettent de calculer le taux de défaillance dans toutes conditions, en appliquant des modèles de contrainte qui tiennent compte des conditions de fonctionnement réelles. La présente norme donne également des recommandations concernant les méthodes pour constituer une base de données de taux de défaillance des composants afin que les taux fournis puissent être employés avec les modèles de contrainte fournis. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- l'addition de plusieurs types de composants et l'actualisation des modèles pour nombreux types de composants;
- l'addition des annexes relatives aux prévisions de fiabilité, des sources des données de taux de défaillance et des informations relatives au classification des composants.

General Information

• Status: Published
• Publication Date: 23-Jun-2011
• ICS: 31.020 - Electronic components in general
• Technical Committee: TC 56 - Dependability
• Drafting Committee: WG 2 - TC 56/WG 2
• Current Stage: DELPUB - Deleted Publication
• Completion Date: 17-Feb-2017

Relations

• Revised: IEC 61709:2017 - Electric components - Reliability - Reference conditions for failure rates and stress models for conversion
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61709
®

Edition 2.0 2011-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE


Electric components – Reliability – Reference conditions for failure rates and
stress models for conversion

Composants électriques – Fiabilité – Conditions de référence pour les taux
de défaillance et modèles de contraintes pour la conversion

IEC 61709:2011

---------------------- Page: 1 ----------------------
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IEC 61709
®

Edition 2.0 2011-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE


Electric components – Reliability – Reference conditions for failure rates and
stress models for conversion

Composants électriques – Fiabilité – Conditions de référence pour les taux
de défaillance et modèles de contraintes pour la conversion

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XD
ICS 31.020 ISBN 978-2-88912-551-7

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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– 2 – 61709 © IEC:2011
CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 9
2 Normative references . 9
3 Terms, definitions and symbols . 10
3.1 Terms and definitons . 10
3.2 Symbols . 12
4 Context and conditions . 13
4.1 Failure modes . 13
4.2 Operating profile considerations . 14
4.3 Storage conditions . 14
4.4 Environmental conditions . 14
5 Generic reference conditions and stress models . 16
5.1 Recommended generic reference conditions . 16
5.2 Generic stress models . 17
5.2.1 General . 17
5.2.2 Stress factor for voltage dependence, π . 18
U
5.2.3 Stress factor for current dependence, π . 18
I
5.2.4 Stress factor for temperature dependence, π . 18
T
5.2.5 Environmental application factor, π . 20
E
5.2.6 Other factors of influence . 21
6 Specific reference conditions and stress models. 21
6.1 Integrated semiconductor circuits . 21
6.1.1 Reference conditions . 21
6.1.2 Stress factors . 23
6.2 Discrete semiconductors . 27
6.2.1 Reference conditions . 27
6.2.2 Stress factors . 28
6.3 Optoelectronic components . 32
6.3.1 Reference conditions . 32
6.3.2 Stress factors . 34
6.4 Capacitors . 38
6.4.1 Reference conditions . 38
6.4.2 Stress factors . 38
6.5 Resistors and resistor networks . 41
6.5.1 Reference conditions . 41
6.5.2 Stress factors . 42
6.6 Inductors, transformers and coils . 43
6.6.1 Reference conditions . 43
6.6.2 Stress factors . 43
6.7 Microwave devices . 44
6.7.1 Reference conditions . 44
6.7.2 Stress factors . 45
6.8 Other passive components . 45
6.8.1 Reference conditions . 45

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61709 © IEC:2011 – 3 –
6.8.2 Stress factors . 45
6.9 Electrical connections. 45
6.9.1 Reference conditions . 45
6.9.2 Stress factors . 46
6.10 Connectors and sockets . 46
6.10.1 Reference conditions . 46
6.10.2 Stress factors . 46
6.11 Relays . 46
6.11.1 Reference conditions . 46
6.11.2 Stress factors . 47
6.12 Switches and push-buttons . 49
6.12.1 Reference conditions . 49
6.12.2 Stress factors . 50
6.13 Signal and pilot lamps . 51
6.13.1 Reference conditions . 51
6.13.2 Stress factors . 51
Annex A (normative) Failure modes of components . 53
Annex B (informative) Failure rate prediction . 55
Annex C (informative) Considerations for the design of a data base on failure rates . 65
Annex D (informative) Potential sources of failure rate data and methods of selection . 68
Annex E (informative) Overview of component classification . 74
Annex F (informative) Examples . 86
Bibliography . 88

Figure 1 – Selection of stress regions in accordance with current and voltage-operating
conditions . 48
Figure 2 – Selection of stress regions in accordance with current and voltage-operating
conditions . 50
Figure B.1 – Stress profile . 59
Figure B.2 – Averaging failure rates . 60

Table 1 – Basic environments . 15
Table 2 – Values of environmental parameters for basic environments . 15
Table 3 – Recommended reference conditions for environmental and mechanical
stresses . 17
Table 4 – Environmental application factor, π . 20
E
Table 5 – Memory . 21
Table 6 – Microprocessors and peripherals, microcontrollers and signal processors . 22
Table 8 – Analog integrated circuits (IC) . 23
Table 9 – Application-specific ICs (ASICs) . 23
Table 10 – Constants for voltage dependence . 24
Table 11– Factor π for digital CMOS-family ICs . 24
U
Table 12 – Factor π for bipolar analog ICs . 24
U
Table 13 – Constants for temperature dependence . 24

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– 4 – 61709 © IEC:2011
for ICs (without EPROM; FLASH-EPROM; OTPROM; EEPROM;
Table 14 – Factor π
T
EAROM) . 26
Table 15 – Factor π for EPROM, FLASH-EPROM, OTPROM, EEPROM, EAROM. 26
T
Table 16 – Transistors common, low frequency. 27
Table 17 – Transistors, microwave, e.g. RF >800 MHz. 27
Table 18 – Diodes . 28
Table 19 – Power semiconductors . 28
Table 20 − Constants for voltage dependence of transistors . 29
Table 21 – Factor π for transistors . 29
U
Table 22 – Constants for temperature dependence of discrete semiconductors . 29
Table 23 – Factor π for transistors, reference and microwave diodes . 31
T
Table 24 – Factor for diodes (without reference and microwave diodes) and power
π
T
semiconductors . 31
Table 25 – Optoelectronic semiconductor signal receivers . 32
Table 26 – LEDs, IREDs, laser diodes and transmitter components . 33
Table 27 – Optocouplers and light barriers. 33
Table 28 – Passive optical components . 34
Table 29 – Transceiver, transponder and optical sub-equipment . 34
Table 30 – Constants for voltage dependence of phototransistors . 35
Table 31 – Factor π for phototransistors . 35
U
Table 32 – Constants for current dependence of LEDs and IREDs . 35
Table 33 – Factor π for LEDs and IREDs . 35
I
Table 34 – Constants for temperature dependence of optoelectronic components . 36
Table 35 – Factor π for optical components . 37
T
Table 36 – Capacitors . 38
Table 37 – Constants for voltage dependence of capacitors . 39
Table 38 – Factor π for capacitors . 39
U
Table 39 – Constants for temperature dependence of capacitors . 40
Table 40 – Factor π for capacitors . 41
T
Table 41 – Resistors and resistor networks . 42
Table 42 – Constants for temperature dependence of resistors . 42
Table 43 – Factor π for resistors . 43
Τ
Table 44 – Inductors, transformers and coils . 43
Table 45 – Constants for temperature dependence of inductors, transformers and coils . 43
Table 46 – Factor π for inductors, transformers and coils . 44
Τ
Table 47 – Microwave devices . 44
Table 48 – Other passive components . 45
Table 49 – Electrical connections. 46
Table 50 – Connectors and sockets . 46
Table 51 – Relays . 47
Table 52 – Factor π for low current relays. 48
ES

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61709 © IEC:2011 – 5 –
Table 53 – Factor π for general purpose relays . 48
ES
Table 54 – Factor π for automotive relays . 49
ES
Table 55 – Constants for temperature dependence of relays . 49
Table 56 – Facteur π for relays . 49
T
Table 57 – Switches and push-buttons . 50
Table 58 – Factor π for switches and push-buttons for low electrical stress . 51
ES
Table 59 – Factor π for switches and push-buttons for higher electrical stress . 51
ES
Table 60 – Signal and pilot lamps . 51
Table 61 – Factor π for signal and pilot lamps . 52
U
Table A.1 – Failure modes – Integrated circuits (ICs)(digital) . 53
Table A.2 – Failure modes – Transistors, diodes, optocouplers . 53
Table A.3 – Failure modes – Capacitors . 54
Table A.4 – Failure modes – Resistors, inductive devices, relays . 54
Table C.1 – Reliability prediction database attributes . 66
Table D.1 – Sources of reliability data (in alphabetical order) . 70
Table E.1 – Classification tree (IEC 61360). 75

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– 6 – 61709 © IEC:2011
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

ELECTRIC COMPONENTS –
RELIABILITY –
REFERENCE CONDITIONS FOR FAILURE RATES
AND STRESS MODELS FOR CONVERSION


FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61709 has been prepared by IEC technical committee 56:
Dependability.
This second edition cancels and replaces the first edition, published in 1996 and constitutes a
technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
– the addition of a number of component types and the updating of models for a large
number of component types;
– the addition of annexes on reliability prediction, sources of failure rate data and
component classification information.

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61709 © IEC:2011 – 7 –
The text of this standard is based on the following documents:
FDIS Report on voting
56/1422/FDIS 56/1431/RVD

Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

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– 8 – 61709 © IEC:2011
INTRODUCTION
This International Standard is intended for the reliability prediction of components as used in
equipment and is aimed at organizations that have their own data and describes how to state
and use that data in order to perform reliability predictions.
It can also be used to allow an organization to set up a failure rate database and describes
the reference conditions for which field failure rates should be stated. The reference
conditions adopted in this standard are typical of the majority of applications of components in
equipment however when components operate under other conditions the users may consider
stating these conditions as their reference conditions.
Using the presented stress models allows extrapolation of failure rates to other operating
conditions which in turn permits the prediction of failure rates at assembly level. This allows
estimation of the effect of design changes or changes in the environmental conditions on
component reliability. Reliability prediction is most useful in the early design phase of
electrical equipment. It can be used, for example, to identify potential reliability problems, the
planning of logistic support strategies and the evaluation of designs.
The stress models contained herein are generic and are as simple as possible while still being
comparable with more complex equations contained in other models.
This standard does not contain failure rates, but it describes how they can be stated and
used. This approach allows a user to select the most relevant and up to date failure rates for
the prediction from a source that they select. This standard also contains information on how
to select the data that can be used in the presented models.

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61709 © IEC:2011 – 9 –
ELECTRIC COMPONENTS –
RELIABILITY –
REFERENCE CONDITIONS FOR FAILURE RATES
AND STRESS MODELS FOR CONVERSION



1 Scope
This International Standard gives guidance on how failure rate data can be employed for
reliability prediction of electric components in equipment.
Reference conditions are numerical values of stresses that are typically observed by
components in the majori
...