EN 61709:2017

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

NEW!IEC 61709:2017 is available as IEC 61709:2017 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.IEC 61709:2017 gives guidance on the use of failure rate data for reliability prediction of electric components used in equipment. The method presented in this document uses the concept of reference conditions which are the typical values of stresses that are observed by components in the majority of applications. Reference conditions are useful since they provide a known standard basis from which failure rates can be modified to account for differences in environment from the environments taken as reference conditions. Each user can use the reference conditions defined in this document or use their own. When failure rates stated at reference conditions are used it allows realistic reliability predictions to be made in the early design phase. The stress models described herein are generic and can be used as a basis for conversion of failure rate data given at these reference conditions to actual operating conditions when needed and this simplifies the prediction approach. Conversion of failure rate data is only possible within the specified functional limits of the components. This document 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. Reference conditions for failure rate data are specified, so that data from different sources can be compared on a uniform basis. If failure rate data are given in accordance with this document then additional information on the specified conditions can be dispensed with. This document does not provide base failure rates for components – rather it provides models that allow failure rates obtained by other means to be converted from one operating condition to another operating condition. The prediction methodology described in this document assumes that the parts are being used within its useful life. The methods in this document have a general application but are specifically applied to a selection of component types as defined in Clauses 6 to 20 and I.2. This third edition cancels and replaces the second edition, published in 2011. This edition constitutes a technical revision. This third edition is a merger of IEC 61709:2011 and IEC TR 62380:2004. This edition includes the following significant technical changes with respect to the previous edition: addition of 4.5 Components choice, 4.6 Reliability growth during the deployment phase of new equipment, 4.7 How to use this document, and of Clause 19 Printed circuit boards (PCB) and Clause 20 Hybrid circuits with respect to IEC TR 62380; addition of failure modes of components in Annex A; modification of Annex B, Thermal model for semiconductors, adopted and revised from IEC TR 62380; modification of Annex D, Considerations on mission profile; modification of Annex E, Useful life models, adopted and revised from IEC TR 62380; revision of Annex F (former B.2.6.4), Physics of failure; addition of Annex G (former Annex C), Considerations for the design of a data base on failure rates, complemented with parts of IEC 60319; addition of Annex H, Potential sources of failure rate data and methods of selection; addition of Annex J, Presentation of component reliability data, based on IEC 60319. Keywords: failure rate data, reliability prediction of electric components

Elektrische Bauelemente - Zuverlässigkeit - Referenzbedingungen für Ausfallraten und Beanspruchungsmodelle zur Umrechnung

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

NEW!IEC 61709:2017 est disponible sous forme de IEC 61709:2017 RLV qui contient la Norme internationale et sa version Redline, illustrant les modifications du contenu technique depuis l'édition précédente.IEC 61709:2017 donne des recommandations concernant l'utilisation des données de taux de défaillance pour les prévisions de fiabilité de composants électriques utilisés dans les équipements. La méthode exposée dans le présent document utilise le concept des conditions de référence, qui sont les valeurs typiques des contraintes observées sur les composants dans la plupart des applications. Les conditions de référence sont utiles dans la mesure où elles fournissent une base normalisée connue à partir de laquelle les taux de défaillance peuvent être modifiés afin de prendre en compte les différences observées dans l'environnement en fonction des environnements pris comme conditions de référence. Chaque utilisateur peut appliquer les conditions de référence définies dans le présent document ou bien appliquer ses propres conditions de référence. Lorsque les taux de défaillance indiqués dans les conditions de référence sont utilisés, cela permet de réaliser des prévisions de fiabilité réalistes dès la première phase de conception. Les modèles de contraintes décrits dans le présent document sont génériques et peuvent être utilisés comme base de conversion des données de taux de défaillance dans ces conditions de référence, dans des conditions de fonctionnement réelles si nécessaire, ce qui simplifie l'approche prévisionnelle. La conversion des données de taux de défaillance n'est possible que dans les limites de fonctionnement spécifiées pour les composants. Le présent document 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 contraintes fournis. Les conditions de référence pour les données de taux de défaillance sont définies, de façon à permettre de comparer, dans des conditions uniformes, des données d'origines différentes. Si les données de taux de défaillance sont fournies conformément au présent document, il est possible de se dispenser d'information supplémentaire sur les conditions définies Le présent document ne fournit pas des taux de défaillance de base pour les composants; elle fournit en revanche des modèles qui permettent de convertir les taux de défaillance obtenus par d'autres moyens d’une condition de fonctionnement à l’autre. La méthodologie de prévision décrite dans le présent document pose comme hypothèse l'utilisation des éléments au cours de leur durée de vie. Les méthodes décrites dans le présent document ont une application générale, mais s’appliquent spécifiquement à une sélection de types de composants définis de l’Article 6 à l’Article 20 et en I.2. Cette troisième édition annule et remplace la deuxième édition, parue en 2011. Cette édition constitue une révision technique. Cette troisième édition constitue une fusion entre l’IEC 61709:2011 et l’IEC TR 62380:2004. Cette édition inclut les modifications techniques majeures suivantes par rapport à l’édition précédente: ajout de 4.5 Choix des composants, 4.6 Croissance de la fiabilité pendant la phase de déploiement du nouvel équipement, 4.7 Méthode d’utilisation du présent docume

Električne komponente - Zanesljivost - Referenčni pogoji za pogostost odpovedi in modele obremenjevanja za pretvarjanje (IEC 61709:2017)

Ta dokument podaja napotke o uporabi podatkov o pogostosti odpovedi za napoved zanesljivosti električnih komponent v opremi.
Metoda, predstavljena v tem dokumentu, uporablja koncept referenčnih pogojev, ki so tipične vrednosti obremenitev, ki se pojavljajo pri komponentah v večini načinov uporabe.
Referenčni pogoji so uporabni, ker podajajo poznano osnovo standarda, na podlagi katere se lahko spremenijo pogostosti odpovedi, da se upoštevajo razlike okolja od okolij, ki predstavljajo referenčne pogoje. Vsak uporabnik lahko uporabi referenčne pogoje, določene v tem dokumentu, ali lastne referenčne pogoje. Kadar so v referenčnih pogojih uporabljene pogostosti odpovedi, to omogoča realistično napoved zanesljivosti v zgodnji fazi načrtovanja.
V tem dokumentu opisani modeli obremenjevanja so generični in se lahko po potrebi uporabijo kot osnova za pretvarjanje podatkov o pogostosti odpovedi, podanih v teh referenčnih pogojih, v dejanske obratovalne pogoje, kar poenostavlja pristop k napovedi. Pretvarjanje podatkov o pogostosti odpovedi je mogoče le znotraj podanih funkcijskih omejitev komponent.
Ta dokument podaja tudi napotke, kako zdelati zbirko podatkov o odpovedih komponent, ki podaja pogostosti odpovedi, ki se lahko uporabijo z vključenimi modeli obremenjevanja.
Referenčni pogoji za podatke o pogostosti odpovedi so podani, tako da je mogoče podatke iz drugih virov primerjati na enotni osnovi. Če so podatki o pogostosti odpovedi podani v skladu s tem dokumentom, se lahko dodatne informacije o podanih pogojih izpustijo.
Ta dokument ne podaja osnovnih pogostosti odpovedi za komponente, ampak podaja modele, ki omogočajo pretvarjanje pogostosti odpovedi, pridobljenih z drugimi sredstvi, iz enega obratovalnega pogoja v drug obratovalni pogoj.
Metodologija napovedi, opisana v tem dokumentu, predpostavlja, da se deli uporabljajo v življenjski dobi. Metode v tem dokumentu so splošno uporabne, vendar se uporabljajo posebej za izbiro tipov komponent, kot določajo točke od 6 do 20 in točka I.2.

General Information

• Status: Published
• Publication Date: 18-May-2017
• Withdrawal Date: 23-Mar-2020
• ICS: 31.020 - Electronic components in general
• Technical Committee: CLC/SR 56 - Dependability
• Drafting Committee: IEC/TC 56 - IEC_TC_56
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 19-May-2017
• Completion Date: 19-May-2017
• Ref Project: SIST EN 61709:2017 - Electric components - Reliability - Reference conditions for failure rates and stress models for conversion (IEC 61709:2017)

Relations

• Replaces: EN 61709:2011 - Electric components - Reliability - Reference conditions for failure rates and stress models for conversion
• Effective Date: 07-Jun-2022
• Corrected By: EN 61709:2017/AC:2019-11 - Electric components - Reliability - Reference conditions for failure rates and stress models for conversion
• Effective Date: 05-Nov-2019

EN 61709:2017 - Overview

Standard reference: EN 61709:2017 (IEC 61709:2017 RLV)
Title: Electric components - Reliability - Reference conditions for failure rates and stress models for conversion
Organization: CLC / IEC

EN 61709:2017 provides guidance for using failure rate data to support realistic reliability prediction of electric components. The standard defines a set of reference conditions (typical stress values observed in most applications) and presents generic and component‑specific stress models to convert failure rates between reference and actual operating conditions. This third edition merges IEC 61709:2011 with IEC TR 62380:2004 and is a technical revision with new clauses and annexes.

Key topics and requirements

• Reference conditions: Recommended baseline stresses so failure rate data from different sources can be compared uniformly.
• Stress models for conversion: Generic factors for voltage, current, temperature, environment, switching rate and electrical stress to convert failure rates from reference to real conditions.
• Component coverage: Generic models plus specific guidance for component classes (Clauses 6–20) including integrated circuits, discrete semiconductors, optoelectronic components, capacitors, resistors, connectors, relays, printed circuit boards (PCB), and hybrid circuits.
• Annexes and technical aids: Failure modes (Annex A), thermal model for semiconductors (Annex B), mission profile and useful life considerations, physics of failure, database design, sources and presentation of failure rate data.
• Limits and assumptions: The document does not provide base failure rates; it assumes parts are within their useful life and conversion is only valid within components’ functional limits.
• Data management: Guidance for constructing failure‑rate databases and selecting source data to ensure consistent reliability prediction.

Applications

• Early‑phase reliability prediction during electronic product design.
• Converting vendor, field or laboratory failure rate data to project‑specific operating conditions.
• Creating or harmonizing component failure‑rate databases for system reliability assessment.
• Supporting maintenance planning, safety studies and dependability analyses in electronics systems.

Who should use this standard?

• Reliability and design engineers in electronics and electro‑technical industries
• Component manufacturers and suppliers preparing or evaluating failure rate data
• System integrators, maintainers and safety engineers requiring consistent reliability estimates
• Test labs and data managers building failure‑rate databases

Related standards (selected)

EN 61709 references several IEC standards used for dependability and component data, such as IEC 60300‑3‑2, IEC 60300‑3‑3, IEC 60721 series, IEC 61360, IEC 61508 and others for harmonized application and data presentation.

Keywords: failure rate data, reliability prediction of electric components, reference conditions, stress models, component failure rates, thermal model, PCB, hybrid circuits.

Standards Content (Sample)

SLOVENSKI STANDARD
01-julij-2017
1DGRPHãþD
SIST EN 61709:2011
(OHNWULþQHNRPSRQHQWH=DQHVOMLYRVW5HIHUHQþQLSRJRML]DSRJRVWRVWRGSRYHGLLQ
PRGHOHREUHPHQMHYDQMD]DSUHWYDUMDQMH,(&
Electric components - Reliability - Reference conditions for failure rates and stress
models for conversion (IEC 61709:2017)
Elektrische Bauelemente - Zuverlässigkeit - Referenzbedingungen für Ausfallraten und
Beanspruchungsmodelle zur Umrechnung (IEC 61709:2017)
Composants électriques - Fiabilité - Conditions de référence pour les taux de défaillance
et modèles de contraintes pour la conversion (IEC 61709:2017)
Ta slovenski standard je istoveten z: EN 61709:2017
ICS:
21.020 =QDþLOQRVWLLQQDþUWRYDQMH Characteristics and design of
VWURMHYDSDUDWRYRSUHPH machines, apparatus,
equipment
31.020 Elektronske komponente na Electronic components in
splošno general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN 61709
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2017
ICS 31.020 Supersedes EN 61709:2011
English Version
Electric components - Reliability - Reference conditions for
failure rates and stress models for conversion
(IEC 61709:2017)
Composants électriques - Fiabilité - Conditions de référence Bauelemente der Elektronik - Zuverlässigkeit -
pour les taux de défaillance et modèles de contraintes pour Referenzbedingungen für Ausfallraten und
la conversion Beanspruchungsmodelle zur Umrechnung
(IEC 61709:2017) (IEC 61709:2017)
This European Standard was approved by CENELEC on 2017-03-24. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2017 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 61709:2017 E
European foreword
The text of document 56/1714/FDIS, future edition 3 of IEC 61709, prepared by
IEC/TC 56 "Dependability" was submitted to the IEC-CENELEC parallel vote and approved by
CENELEC as EN 61709:2017.
The following dates are fixed:
(dop) 2017-12-24
• latest date by which the document has to be
implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2020-03-24
standards conflicting with the
document have to be withdrawn
This document supersedes EN 61709:2011.

Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights
Endorsement notice
The text of the International Standard IEC 61709:2017 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:

IEC 60300-3-2:2004 NOTE Harmonized as EN 60300-3-2:2005.
IEC 60300-3-3 NOTE Harmonized as EN 60300-3-3.
IEC 60721 (series) NOTE Harmonized as EN 60721 (series).
IEC 60721-3-3 NOTE Harmonized as EN 60721-3-3.
IEC 60721-3-4 NOTE Harmonized as EN 60721-3-4.
IEC 60721-3-5 NOTE Harmonized as EN 60721-3-5.
IEC 60721-3-7 NOTE Harmonized as EN 60721-3-7.
IEC 61014:2003 NOTE Harmonized as EN 61014:2003.
IEC 61360 (series) NOTE Harmonized as EN 61360 (series).
IEC 61360-1:2009 NOTE Harmonized as EN 61360-1:2010.
IEC 61360-4:2005 NOTE Harmonized as EN 61360-4:2005.
IEC 61508 (series) NOTE Harmonized as EN 61508 (series).
IEC 61649:2008 NOTE Harmonized as EN 61649:2008.
IEC 61703:2002 NOTE Harmonized as EN 61703:2002.
IEC 61710 NOTE Harmonized as EN 61710.
IEC 61810-2:2011 NOTE Harmonized as EN 61810-2:2011.
IEC 61810-2-1:2011 NOTE Harmonized as EN 61810-2-1:2011.
IEC 62007 (series) NOTE Harmonized as EN 62007 (series).
IEC 62741 NOTE Harmonized as EN 62741.
IEC 62308:2006 NOTE Harmonized as EN 62308:2006.

Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
NOTE 1 When an International Publication has been modified by common modifications, indicated by (mod), the relevant

EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60050-192 2015 International electrotechnical vocabulary - - -
Part 192: Dependability
IEC 61709 ®
Edition 3.0 2017-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
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
INTERNATIONALE
ICS 31.020 ISBN 978-2-8322-3902-5

– 2 – IEC 61709:2017 © IEC 2017
CONTENTS
FOREWORD . 9
INTRODUCTION . 11
1 Scope . 12
2 Normative references . 12
3 Terms, definitions and symbols . 12
3.1 Terms and definitions. 12
3.2 Symbols . 16
4 Context and conditions . 17
4.1 Failure modes and mechanisms . 17
4.2 Thermal modelling . 18
4.3 Mission profile consideration . 18
4.3.1 General . 18
4.3.2 Operating and non-operating conditions . 18
4.3.3 Dormancy . 19
4.3.4 Storage . 19
4.4 Environmental conditions . 19
4.5 Components choice . 21
4.6 Reliability growth during the deployment phase of new equipment . 22
4.7 How to use this document . 23
5 Generic reference conditions and stress models . 24
5.1 Recommended generic reference conditions . 24
5.2 Generic stress models . 25
5.2.1 General . 25
5.2.2 Stress factor for voltage dependence, π . 26
U
5.2.3 Stress factor for current dependence, π . 26
I
5.2.4 Stress factor for temperature dependence, π . 26
T
5.2.5 Environmental application factor, π . 28
E
5.2.6 Dependence on switching rate, π . 28
S
5.2.7 Dependence on electrical stress, . 29
π
ES
5.2.8 Other factors of influence . 29
6 Integrated semiconductor circuits . 29
6.1 Specific reference conditions . 29
6.2 Specific stress models . 31
6.2.1 General . 31
6.2.2 Voltage dependence, factor . 32
π
U
6.2.3 Temperature dependence, factor . 32
π
T
7 Discrete semiconductors . 35
7.1 Specific reference conditions . 35
7.2 Specific stress models . 36
7.2.1 General . 36
7.2.2 Voltage dependence for transistors, factor π . 37
U
7.2.3 Temperature dependence, factor π . 37
T
8 Optoelectronic components . 39

IEC 61709:2017 © IEC 2017 – 3 –
8.1 Specific reference conditions . 39
8.2 Specific stress models . 41
8.2.1 General . 41
8.2.2 Voltage dependence, factor π . 41
U
8.2.3 Current dependence, factor π . 41
I
8.2.4 Temperature dependence, factor π . 42
T
9 Capacitors . 44
9.1 Specific reference conditions . 44
9.2 Specific stress model . 44
9.2.1 General . 44
9.2.2 Voltage dependence, factor π . 44
U
9.2.3 Temperature dependence, factor π . 46
T
10 Resistors and resistor networks . 47
10.1 Specific reference conditions . 47
10.2 Specific stress models . 48
10.2.1 General . 48
10.2.2 Temperature dependence, factor π . 48
T
11 Inductors, transformers and coils . 49
11.1 Reference conditions . 49
11.2 Specific stress model . 49
11.2.1 General . 49
11.2.2 Temperature dependence, factor π . 49
T
12 Microwave devices . 50
12.1 Specific reference conditions . 50
12.2 Specific stress models . 51
13 Other passive components . 51
13.1 Specific reference conditions . 51
13.2 Specific stress models . 51
14 Electrical connections . 51
14.1 Specific reference conditions . 51
14.2 Specific stress models . 52
15 Connectors and sockets . 52
15.1 Reference conditions . 52
15.2 Specific stress models . 52
16 Relays . 52
16.1 Reference conditions . 52
16.2 Specific stress models . 53
16.2.1 General . 53
16.2.2 Dependence on switching rate, factor π . 53
S
16.2.3 Dependence on electrical stress, factor π . 54
ES
16.2.4 Temperature dependence, factor π . 55
T
17 Switches and push-buttons . 55
17.1 Specific reference conditions . 55
17.2 Specific stress model . 56
17.2.1 General . 56

– 4 – IEC 61709:2017 © IEC 2017
17.2.2 Dependence on electrical stress, factor π . 56
ES
18 Signal and pilot lamps . 57
18.1 Specific reference conditions . 57
18.2 Specific stress model . 57
18.2.1 General . 57
18.2.2 Voltage dependence, factor π . 58
U
19 Printed circuit boards (PCB) . 58
20 Hybrid circuits . 58
Annex A (normative) Failure modes of components . 59
Annex B (informative) Thermal model for semiconductors . 62
B.1 Thermal model . 62
B.2 Junction temperature calculation . 63
B.3 Thermal resistance evaluation . 64
B.4 Power dissipation of an integrated circuit P . 65
Annex C (informative) Failure rate prediction . 68
C.1 General . 68
C.2 Failure rate prediction for assemblies . 68
C.2.1 General . 68
C.2.2 Assumptions and limitations . 69
C.2.3 Process for failure rate prediction . 69
C.2.4 Prediction models . 70
C.2.5 Other methods of reliability prediction . 71
C.2.6 Validity considerations of reliability models and predictions . 72
C.3 Component considerations . 73
C.3.1 Component model . 73
C.3.2 Components classification . 73
C.4 General consideration about failure rate . 73
C.4.1 General . 73
C.4.2 General behaviour of the failure rate of components . 74
C.4.3 Expected values of failure rate. 75
C.4.4 Sources of variation in failure rates . 75
Annex D (informative) Considerations on mission profile . 77
D.1 General . 77
D.2 Dormancy . 77
D.3 Mission profile . 78
D.4 Example of mission profile . 79
Annex E (informative) Useful life models . 80
E.1 General . 80
E.2 Power transistors . 80
E.3 Optocouplers . 80
E.3.1 Useful life L . 80
E.3.2 Factor L . 81
E.3.3 Factor κ . 81
E.3.4 Factor κ . 82
E.3.5 Factor κ . 82
E.3.6 Factor κ . 82
E.4 LED and LED modules . 83

IEC 61709:2017 © IEC 2017 – 5 –
E.4.1 Useful life L . 83
E.4.2 Factor L . 83
E.4.3 Factor κ . 84
E.4.4 Factor κ . 84
E.4.5 Factor κ . 85
E.4.6 Factor κ . 85
E.5 Aluminium, non-solid electrolyte capacitors . 85
E.6 Relays . 86
E.7 Switches and keyboards . 86
E.8 Connectors . 86
Annex F (informative) Physics of failure . 87
F.1 General . 87
F.2 Failure mechanisms of integrated circuits . 88
Annex G (informative) Considerations for the design of a data base on failure rates . 89
G.1 General . 89
G.2 Data collection acquisition – collection process . 89
G.3 Which data to collect and how to collect it . 89
G.4 Calculation and decision making . 90
G.5 Data descriptions . 90
G.6 Identification of components . 90
G.6.1 General . 90
G.6.2 Component identification . 91
G.6.3 Component technology . 91
G.7 Specification of components . 91
G.7.1 General . 91
G.7.2 Electrical specification of components . 91
G.7.3 Environmental specification of components . 92
G.8 Field related issues data . 92
G.8.1 General . 92
G.8.2 Actual field conditions . 92
G.8.3 Data on field failures . 92
G.9 Test related issues data . 93
G.9.1 General . 93
G.9.2 Actual test conditions . 93
G.9.3 Data on test failures . 93
G.10 Failure rate database attributes . 94
Annex H (informative) Potential sources of failure rate data and methods of selection . 96
H.1 General . 96
H.2 Data source selection . 96
H.3 User data . 97
H.4 Manufacturer’s data . 97
H.5 Handbook reliability data . 98
H.5.1 General . 98
H.5.2 Using handbook data with this document . 98
H.5.3 List of available handbooks . 99
Annex I (informative) Overview of component classification . 102
I.1 General . 102
I.2 The IEC 61360 system . 102

– 6 – IEC 61709:2017 © IEC 2017
I.3 Other systems. 110
I.3.1 General . 110
I.3.2 NATO stock numbers . 110
I.3.3 UNSPSC codes . 110
I.3.4 STEP/EXPRESS . 110
I.3.5 IECQ . 110
I.3.6 ECALS . 111
I.3.7 ISO 13584 . 111
I.3.8 MIL specifications . 111
Annex J (informative) Presentation of component reliability data . 112
J.1 General . 112
J.2 Identification of components . 112
J.2.1 General . 112
J.2.2 Component identification . 113
J.2.3 Component technology . 113
J.3 Specification of components . 113
J.3.1 General . 113
J.3.2 Electrical specification of components . 113
J.3.3 Environmental specification of components . 113
J.4 Test related issues data . 113
J.4.1 General . 113
J.4.2 Actual test conditions . 114
J.5 Data on test failures . 114
Annex K (informative) Examples . 116
K.1 Integrated circuit . 116
K.2 Transistor . 116
K.3 Capacitor . 116
K.4 Relay . 117
Bibliography . 118

Figure 1 – Comparison of the temperature dependence of π for CMOS IC. 24
T
Figure 2 – Selection of stress regions in accordance with current and voltage-operating
conditions . 54
Figure 3 – Selection of stress regions in accordance with current and voltage-operating
conditions . 56
Figure B.1 – Temperatures inside equipment . 63
Figure B.2 – Thermal resistance model . 64
Figure D.1 – Mission profile . 79

Table 1 – Basic environments . 20
Table 2 – Values of environmental parameters for basic environments . 21
Table 3 – Recommended reference conditions for environmental and mechanical
stresses . 25
Table 4 – Environmental application factor, π . 28
E
Table 5 – Memory . 30
Table 6 – Microprocessors and peripherals, microcontrollers and signal processors . 30
Table 7 – Digital logic families and bus interfaces, bus driver and receiver circuits . 30

IEC 61709:2017 © IEC 2017 – 7 –
Table 8 – Analog ICs . 31
Table 9 – Application-specific ICs (ASICs) . 31
Table 10 – Constants for voltage dependence . 32
Table 11 – Factor for digital CMOS-family ICs . 32
π
U
Table 12 – Factor π for bipolar analog ICs . 32
U
Table 13 – Constants for temperature dependence . 32
Table 14 – Factor π for ICs (without EPROM; FLASH-EPROM; OTPROM; EEPROM;
T
EAROM) . 34
Table 15 – Factor π for EPROM; FLASH-EPROM; OTPROM; EEPROM; EAROM. 34
T
Table 16 – Transistors common, low frequency. 35
Table 17 – Transistors, microwave, (e.g. RF > 800 MHz) . 35
Table 18 – Diodes . 36
Table 19 – Power semiconductors . 36
Table 20 – Constants for voltage dependence of transistors . 37
Table 21 – Factor π for transistors . 37
U
Table 22 – Constants for temperature dependence of discrete semiconductors . 37
Table 23 – Factor π for transistors, reference and microwave diodes . 38
T
Table 24 – Factor π for diodes (without reference and microwave diodes) and power
T
semiconductors . 38
Table 25 – Optoelectronic semiconductor signal receivers . 39
Table 26 – LEDs, IREDs, laser diodes and transmitter components . 39
Table 27 – Optocouplers and light barriers. 40
Table 28 – Passive optical components . 40
Table 29 – Transceiver, transponder and optical sub-equipment . 40
Table 30 – Constants for voltage dependence of phototransistors . 41
Table 31 – Factor π for phototransistors . 41
U
Table 32 – Constants for current dependence of LEDs and IREDs . 42
π
Table 33 – Factor for LEDs and IREDs . 42
I
Table 34 – Constants for temperature dependence of optoelectronic components . 42
Table 35 – Factor π for optical components . 43
T
Table 36 – Capacitors . 44
Table 37 – Constants for voltage dependence of capacitors . 45
Table 38 – Factor π for capacitors . 45
U
Table 39 – Constants for temperature dependence of capacitors . 46
Table 40 – Factor π for capacitors . 47
T
Table 41 – Resistors and resistor networks . 48
Table 42 – Constants for temperature dependence of resistors . 48
Table 43 – Factor π for resistors . 49
T
Table 44 – Inductors, transformers and coils . 49
Table 45 – Constants for temperature dependence of inductors, transformers and coils . 49
Table 46 – Factor π for inductors, transformers and coils . 50
T
– 8 – IEC 61709:2017 © IEC 2017
Table 47 – Microwave devices . 50
Table 48 – Other passive components . 51
Table 49 – Electrical connections. 52
Table 50 – Connectors and sockets . 52
Table 51 – Relays . 53
Table 52 – Factor for low current relays . 54
π
ES
Table 53 – Factor π for general purpose relays . 54
ES
Table 54 – Factor π for automotive relays . 55
ES
Table 55 – Constants for temperature dependence of relays . 55
Table 56 – Factor π for relays . 55
T
Table 57 – Switches and push-buttons . 56
Table 58 – Factor for switches and push-buttons for low electrical stress . 57
π
ES
Table 59 – Factor π for switches and push-buttons for higher electrical stress . 57
ES
Table 60 – Signal and pilot lamps . 57
π
Table 61 – Factor for signal and pilot lamps . 58
U
Table A.1 – Failure modes: ICs (digital) . 59
Table A.2 – Failure modes: transistors, diodes, optocouplers . 60
Table A.3 – Failure modes: LEDs . 60
Table A.4 – Failure modes: laser diodes and modules . 60
Table A.5 – Failure modes: photodiodes and receiver modules . 60
Table A.6 – Failure modes: capacitors . 61
Table A.7 – Failure modes: resistors, inductive devices, relays . 61
Table B.1 – Thermal resistance as a function of package type, pin number and airflow
factor . 65
Table B.2 – Typical values of v are K . 65
Table B.3 – Values of P and P . 66
DC f
Table E.1 – Useful life limitations for switches and keyboards . 86
Table F.1 – Failure mechanism for Integrated circuits . 88
Table G.1 – Reliability prediction database attributes . 95
Table H.1 – Result of calculation for transistors common, low frequency. 99
Table H.2 – Sources of reliability data (in alphabetical order) . 99
Table I.1 – Classification tree (IEC 61360-4) . 103

IEC 61709:2017 © IEC 2017 – 9 –
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
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Spec
...