EN IEC 60747-5-5:2020

Semiconductor devices - Part 5-5: Optoelectronic devices - Photocouplers

IEC 60747-5-5:2020(E) specifies the terminology, essential ratings, characteristics, safety tests, as well as the measuring methods for photocouplers. Note: The term "optocoupler" can also be used instead of "photocoupler". This edition includes the following significant technical changes with respect to the previous edition: a) optional data sheet basic insulation rating in accordance with IEC 60664-1:2007, 6.1.3.5; b) editorial corrections on the use of VIORM; c) editorial corrections on Figure 2: Time intervals for method b); d) addition of an alternative surge pulse VIOSM test method.

Halbleiterbauelemente - Teil 5-5: Optoelektronische Bauelemente - Optokoppler

Dispositifs à semiconducteurs - Partie 5-5 : Dispositifs optoélectroniques - Photocoupleurs

L’IEC 60747-5-5:2020 spécifie la terminologie, les valeurs assignées essentielles, les caractéristiques, les essais de sécurité, ainsi que les méthodes de mesure pour les photocoupleurs. NOTE Le terme "optocoupleur" peut aussi être employé à la place de "photocoupleur". Cette édition inclut les modifications techniques majeures suivantes par rapport à l’édition précédente: a) valeur assignée de l’isolation principale, élément facultatif de la fiche technique, consignée conformément à l’IEC 60664-1:2007, 6.1.3.5; b) corrections éditoriales relatives à l’utilisation de VIORM; c) corrections éditoriales à la Figure 2: Intervalles de temps pour la méthode b); d) ajout d’une méthode d’essai en variante pour l’impulsion de tension d’isolement de surcharge VIOSM.

Polprevodniški elementi - 5-5. del: Optoelektronske naprave - Optični sklopniki (IEC 60747-5-5:2020)

General Information

• Status: Published
• Publication Date: 10-Sep-2020
• ICS: 31.080.01 - Semiconductor devices in general
• ICS: 31.260 - Optoelectronics. Laser equipment
• Technical Committee: CLC/TC 47X - Semiconductor devices and trusted chips
• Drafting Committee: IEC/SC 47E - IEC_SC_47E
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 11-Sep-2020
• Completion Date: 11-Sep-2020
• Ref Project: SIST EN IEC 60747-5-5:2020 - Semiconductor devices - Part 5-5: Optoelectronic devices - Photocouplers (IEC 60747-5-5:2020)

Relations

• Replaces: EN 60747-5-5:2011/A1:2015 - Semiconductor devices - Discrete devices - Part 5-5: Optoelectronic devices - Photocouplers
• Effective Date: 15-Sep-2020
• Replaces: EN 60747-5-5:2011 - Semiconductor devices - Discrete devices - Part 5-5: Optoelectronic devices - Photocouplers
• Effective Date: 15-Sep-2020

Overview

EN IEC 60747-5-5:2020 (equivalent to IEC 60747-5-5:2020) is the European/IEC standard for photocouplers (also called optocouplers). It defines terminology, essential ratings, electrical characteristics, safety tests and the measuring methods used to specify and verify optoelectronic isolation devices. The 2020 edition updates insulation-related options and test methods and clarifies editorial points (including VIORM usage and surge test alternatives).

Key topics and requirements

The standard covers practical and testable requirements for photocouplers, including:

• Terminology and symbols used for limiting values and ratings.
• Electrical characteristics for common outputs:
  • Phototransistor outputs (current transfer ratio, saturation voltages, switching times).
  • Phototriac outputs / solid-state opto-relays (off‑state/on‑state voltages, holding current, dV/dt).
• Protection against electric shock:
  • Type identification, datasheet basic insulation rating options (aligned with IEC 60664-1), rated isolation voltages, and safety ratings.
• Measuring methods and test procedures:
  • Current transfer ratio (CTR), input‑to‑output capacitance, isolation resistance, isolation withstand tests, partial discharge measurements, switching-time measurement, peak off‑state/on‑state tests, DC off/on‑state tests, and common‑mode transient immunity (CMTI).
• Test sequences and environmental/endurance tests (routine, sample and type tests), plus circuits and waveforms for reproducible measurement.
• Notable 2020 technical changes:
  • Optional datasheet basic insulation rating per IEC 60664-1:2007 (6.1.3.5).
  • Editorial clarifications on VIORM and timing figures.
  • Addition of an alternative surge pulse VIOSM test method.

Applications and practical value

EN IEC 60747-5-5:2020 is essential for:

• Component manufacturers documenting photocoupler datasheets and declaring insulation/functional ratings.
• Design engineers selecting optocouplers for isolation, signal transfer and safety in power supplies, industrial controls, communications and consumer electronics.
• Test laboratories conducting standardized electrical, environmental and safety tests (e.g., partial discharge, surge, CMTI).
• Compliance & safety professionals aligning product claims with harmonized standards for market access and product safety (notably for equipment meeting IEC 62368-1 and related regulations).

Related standards

Relevant referenced standards include:

• IEC 60664-1 (insulation coordination / basic insulation rating)
• IEC 61000-4-5 (surge immunity test)
• IEC 62368-1 (equipment safety)
• IEC 60068 series (environmental testing) These provide complementary test methods and safety criteria for isolation components.

EN IEC 60747-5-5:2020 is the authoritative reference when specifying, testing or certifying photocouplers/optocouplers for electrical isolation and safety.

Standards Content (Sample)

SLOVENSKI STANDARD
01-november-2020
Nadomešča:
SIST EN 60747-5-5:2011
SIST EN 60747-5-5:2011/A1:2015
Polprevodniški elementi - 5-5. del: Optoelektronske naprave - Optični sklopniki
(IEC 60747-5-5:2020)
Semiconductor devices - Part 5-5: Optoelectronic devices - Photocouplers (IEC 60747-5-
5:2020)
Halbleiterbauelemente - Teil 5-5: Optoelektronische Bauelemente - Optokoppler (IEC
60747-5-5:2020)
Dispositifs à semiconducteurs - Partie 5-5 : Dispositifs optoélectroniques -
Photocoupleurs (IEC 60747-5-5:2020)
Ta slovenski standard je istoveten z: EN IEC 60747-5-5:2020
ICS:
31.080.01 Polprevodniški elementi Semiconductor devices in
(naprave) na splošno general
31.260 Optoelektronika, laserska Optoelectronics. Laser
oprema equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 60747-5-5

NORME EUROPÉENNE
EUROPÄISCHE NORM
September 2020
ICS 31.080.01; 31.260 Supersedes EN 60747-5-5:2011 and all of its
amendments and corrigenda (if any)
English Version
Semiconductor devices - Part 5-5: Optoelectronic devices -
Photocouplers
(IEC 60747-5-5:2020)
Dispositifs à semiconducteurs - Partie 5-5 : Dispositifs Halbleiterbauelemente - Teil 5-5: Optoelektronische
optoélectroniques - Photocoupleurs Bauelemente - Optokoppler
(IEC 60747-5-5:2020) (IEC 60747-5-5:2020)
This European Standard was approved by CENELEC on 2020-08-24. 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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, 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: Rue de la Science 23, B-1040 Brussels
© 2020 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60747-5-5:2020 E

European foreword
The text of document 47E/706/FDIS, future edition 2 of IEC 60747-5-5, prepared by SC 47E "Discrete
semiconductor devices" of IEC/TC 47 "Semiconductor devices" was submitted to the IEC-CENELEC
parallel vote and approved by CENELEC as EN IEC 60747-5-5:2020.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2021-05-24
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2023-08-24
document have to be withdrawn
This document supersedes EN 60747-5-5:2011 and all of its amendments and corrigenda (if any).
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 60747-5-5:2020 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 60065 NOTE Harmonized as EN 60065
IEC 60270:2000 NOTE Harmonized as EN 60270:2001 (not modified)
IEC 60747-5-2 NOTE Harmonized as EN 60747-5-2
IEC 60747-5-3 NOTE Harmonized as EN 60747-5-3
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.
NOTE 1  Where 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 60068-1 2013 Environmental testing - Part 1: General EN 60068-1 2014
and guidance
IEC 60068-2-1 -  Environmental testing - Part 2-1: Tests - EN 60068-2-1 -
Test A: Cold
IEC 60068-2-2 -  Environmental testing - Part 2-2: Tests - EN 60068-2-2 -
Test B: Dry heat
IEC 60068-2-6 -  Environmental testing - Part 2-6: Tests - EN 60068-2-6 -
Test Fc: Vibration (sinusoidal)
IEC 60068-2-14 -  Environmental testing - Part 2-14: Tests - EN 60068-2-14 -
Test N: Change of temperature
IEC 60068-2-17 -  Basic environmental testing procedures - EN 60068-2-17 -
Part 2-17: Tests - Test Q: Sealing
IEC 60068-2-20 -  Environmental testing - Part 2-20: Tests - EN 60068-2-20 -
Test T: Test methods for solderability and
resistance to soldering heat of devices with
leads
IEC 60068-2-27 -  Environmental testing - Part 2-27: Tests - EN 60068-2-27 -
Test Ea and guidance: Shock
IEC 60068-2-30 -  Environmental testing - Part 2-30: Tests - EN 60068-2-30 -
Test Db: Damp heat, cyclic (12 h + 12 h
cycle)
IEC 60068-2-58 -  Environmental testing - Part 2-58: Tests - EN 60068-2-58 -
Test Td: Test methods for solderability,
resistance to dissolution of metallization
and to soldering heat of surface mounting
devices (SMD)
IEC 60068-2-78 -  Environmental testing - Part 2-78: Tests - EN 60068-2-78 -
Test Cab: Damp heat, steady state
IEC 60112 -  Method for the determination of the proof EN 60112 -
and the comparative tracking indices of
solid insulating materials
Publication Year Title EN/HD Year
IEC 60216-1 -  Electrical insulating materials - Thermal EN 60216-1 -
endurance properties - Part 1: Ageing
procedures and evaluation of test results
IEC 60216-2 -  Electrical insulating materials - Thermal EN 60216-2 -
endurance properties - Part 2:
Determination of thermal endurance
properties of electrical insulating materials
- Choice of test criteria
IEC 60664-1 2007 Insulation coordination for equipment EN 60664-1 2007
within low-voltage systems - Part 1:
Principles, requirements and tests
IEC 60672-2 -  Ceramic and glass insulating materials - EN 60672-2 -
Part 2: Methods of test
IEC 60695-11-5 -  Fire hazard testing - Part 11-5: Test flames EN 60695-11-5 -
- Needle-flame test method - Apparatus,
confirmatory test arrangement and
guidance
IEC 61000-4-5 -  Electromagnetic compatibility (EMC) - Part EN 61000-4-5 -
4-5: Testing and measurement techniques
- Surge immunity test
IEC 62368-1 2018 Audio/video, information and EN IEC 62368-1 2020
communication technology equipment -
Part 1: Safety requirements
IEC 60747-5-5 ®
Edition 2.0 2020-07
INTERNATIONAL
STANDARD
Semiconductor devices –
Part 5-5: Optoelectronic devices – Photocouplers

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.080.01; 31.260 ISBN 978-2-8322-8602-9

– 2 – IEC 60747-5-5:2020 © IEC 2020
CONTENTS
FOREWORD . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
3.7 Symbols for limiting values (absolute maximum system) over the operating
temperature range, unless otherwise stated . 16
4 Electrical characteristics . 16
4.1 Phototransistor output photocoupler . 16
4.2 Phototriac output photocoupler or solid state opto-relay . 17
5 Photocouplers providing protection against electric shock . 18
5.1 General . 18
5.2 Type . 18
5.3 Ratings . 18
5.3.1 Datasheet ratings . 18
5.3.2 Safety ratings . 18
5.3.3 Functional ratings . 18
5.3.4 Rated isolation voltages . 18
5.4 Electrical safety requirements . 18
5.5 Electrical, environmental and/or endurance test information (supplementary
information) . 19
5.5.1 Test and test sequence . 19
5.5.2 Routine test . 19
5.5.3 Sample test . 20
5.5.4 Type test . 20
6 Measuring methods for photocouplers . 27
6.1 Current transfer ratio H . 27
f(ctr)
6.2 Input-to-output capacitance C . 28
IO
6.3 Isolation resistance between input and output R . 29
IO
6.4 Isolation test . 30
6.5 Partial discharges of photocouplers . 31
6.6 Collector-emitter saturation voltage V of a photocoupler . 34
CE(sat)
6.6.1 Collector-emitter saturation voltage (DC method) . 34
6.6.2 Collector-emitter saturation voltage (pulse method) . 34
6.7 Switching times t t of a photocoupler . 35
on, off
6.8 Peak off-state current I . 37
DRM
6.9 Peak on-state voltage V . 39
TM
6.10 DC off-state current I . 41
BD
6.11 DC on-state voltage V . 42
T
6.12 Holding current I . 42
H
6.13 Critical rate of rise of off-state voltage dV/dt . 43
6.14 Trigger input current I . 46
FT
6.15 Measuring methods of common mode transient immunity (CMTI) for
photocouplers . 47
7 Testing methods of electrical ratings for phototriac couplers . 49
7.1 Repetitive peak off-state voltage V . 49
DRM
IEC 60747-5-5:2020 © IEC 2020 – 3 –
7.2 DC off-state voltage V . 50
BD
Annex A (normative) Input/output safety test . 51
A.1 Purpose . 51
A.2 Circuit diagram . 51
A.3 Circuit description . 51
A.4 Precautions to be observed . 51
A.5 Measurement procedure . 51
A.6 Specified conditions . 51
Bibliography . 52

Figure 1 – Time intervals for method a) . 12
Figure 2 – Time intervals for method b) . 13
Figure 3 – Test voltage . 15
Figure 4 – Measurement circuit . 27
Figure 5 – Measurement circuit for input to output capacitance . 29
Figure 6 – Measurement circuit for isolation resistance . 29
Figure 7 – Test circuit for withstanding isolation voltage . 30
Figure 8 – Partial discharge test circuit . 31
Figure 9 – Complete test arrangement connections for calibration . 32
Figure 10 – DC measurement circuit . 34
Figure 11 – Pulse measurement circuit . 35
Figure 12 – Switching time measurement circuit . 36
Figure 13 – Switching times . 37
Figure 14 – Measurement circuit for peak off-state current . 38
Figure 15 – Waveforms of the peak off-state voltage and current . 39
Figure 16 – Measurement circuit for peak on-state voltage . 40
Figure 17 – Waveforms of the peak on-state voltage and current . 41
Figure 18 – Measurement circuit for DC off-state current . 41
Figure 19 – Measurement circuit for DC on-state voltage . 42
Figure 20 – Measurement circuit for holding current . 43
Figure 21 – Measurement circuit for critical rate of rise of off-state voltage . 44
Figure 22 – Exponential waveform of the off-voltage (V ) . 45
D
Figure 23 – Linear pulse form of the off-voltage (V ) . 45
D
Figure 24 – Measurement circuit for the trigger input current . 46
Figure 25 – Output terminal voltage versus input forward current . 46
Figure 26 – Common mode transient immunity (CMTI) measurement circuit for
photocoupler . 47
Figure 27 – Typical waveforms of the common mode pulse (V ) and photocoupler
CM
output (V ). 49
O
Figure A.1 – Circuit diagram . 51

Table 1 – Phototransistor electrical characteristics . 16
Table 2 – Phototriac electrical characteristics . 17
Table 3 – Datasheet characteristics . 19

– 4 – IEC 60747-5-5:2020 © IEC 2020
Table 4 – Tests and test sequence for photocoupler providing protection against
electrical shock . 26
Table 5 – Test conditions . 27
Table 6 – Specified conditions for methods a) and b) . 33

IEC 60747-5-5:2020 © IEC 2020 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SEMICONDUCTOR DEVICES –
Part 5-5: Optoelectronic devices –
Photocouplers
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 Specifications (PAS) and Guides (hereafter referred to as "IEC
Publication(s)"). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60747-5-5 has been prepared by subcommittee 47E: Discrete
semiconductor devices, of IEC technical committee 47: Semiconductor devices.
This second edition cancels and replaces the first edition published in 2007 and
Amendment 1:2013. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) optional data sheet basic insulation rating in accordance with IEC 60664-1:2007, 6.1.3.5;
b) editorial corrections on the use of V ;
IORM
c) editorial corrections on Figure 2: Time intervals for method b);
d) addition of an alternative surge pulse V test method.
IOSM
– 6 – IEC 60747-5-5:2020 © IEC 2020
The text of this International Standard is based on the following documents:
FDIS Report on voting
47E/706/FDIS 47E/714/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 60747 series, published under the general title Semiconductor
devices, can be found on the IEC website.
Future standards in this series will carry the new general title as cited above. Titles of existing
standards in this series will be updated at the time of the next edition.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IEC 60747-5-5:2020 © IEC 2020 – 7 –
SEMICONDUCTOR DEVICES –
Part 5-5: Optoelectronic devices –
Photocouplers
1 Scope
This part of IEC 60747 specifies the terminology, essential ratings, characteristics, safety
tests, as well as the measuring methods for photocouplers.
NOTE The term "optocoupler" can also be used instead of "photocoupler".
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the referenced document (including
any amendments) applies.
IEC 60068-1:2013, Environmental testing – Part 1: General and guidance
IEC 60068-2-1, Environmental testing – Part 2-1: Tests – Test A: Cold
IEC 60068-2-2, Environmental testing – Part 2-2: Tests – Test B: Dry heat
IEC 60068-2-6, Environmental testing – Part 2-6: Tests – Test Fc: Vibration (sinusoidal)
IEC 60068-2-14, Environmental testing – Part 2-14: Tests – Test N: Change of temperature
IEC 60068-2-17, Basic environmental testing procedures – Part 2-17: Tests – Test Q: Sealing
IEC 60068-2-20, Environmental testing – Part 2-20: Tests – Test T: Test methods for
solderability and resistance to soldering heat of devices with leads
IEC 60068-2-27, Environmental testing – Part 2-27: Tests – Test Ea and guidance: Shock
IEC 60068-2-30, Environmental testing – Part 2-30: Tests – Test Db: Damp heat, cyclic
(12 h + 12 h cycle)
IEC 60068-2-58, Environmental testing – Part 2-58: Tests – Test Td: Test methods for
solderability, resistance to dissolution of metallization and to soldering heat of surface
mounting devices (SMD)
IEC 60068-2-78, Environmental testing – Part 2-78: Tests – Test Cab: Damp heat, steady
state
IEC 60112, Method for the determination of the proof and the comparative tracking indices of
solid insulating materials
IEC 60216-1, Electrical insulating materials – Thermal endurance properties – Part 1: Ageing
procedures and evaluation of test results

– 8 – IEC 60747-5-5:2020 © IEC 2020
IEC 60216-2, Electrical insulating materials – Thermal endurance properties – Part 2:
Determination of thermal endurance properties of electrical insulating materials – Choice of
test criteria
IEC 60664-1:2007, Insulation coordination for equipment within low-voltage systems – Part 1:
Principles, requirements and tests
IEC 60672-2, Ceramic and glass insulating materials – Part 2: Methods of test
IEC 60695-11-5, Fire hazard testing – Part 11-5: Test flames – Needle-flame test method –
Apparatus, confirmatory test arrangement and guidance
IEC 61000-4-5, Electromagnetic compatibility (EMC) – Part 4-5: Testing and measurement
techniques – Surge immunity test
IEC 62368-1:2018, Audio/video, information and communication technology equipment –
Part 1: Safety requirements
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses: ISO and IEC maintain terminological databases for use in standardization at the
following addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
photocoupler
optoelectronic device designed for the transfer of electrical signals by utilizing optical
radiation to provide coupling with electrical isolation between the input and the output
Note 1 to entry: Different types of photocouplers include ambient-rated or case-rated photocouplers, for
signal-isolation applications.
3.1.1
DC input photocoupler
photocoupler consisting at the input of a photoemitter to which DC current is applied
3.1.2
AC input photocoupler
photocoupler consisting at the input of antiparallel photoemitters to which AC current is
applied
3.1.3
phototransistor output photocoupler
photocoupler whose photosensitive element is a phototransistor
Note 1 to entry: Phototransistor is a transistor in which the current produced by the photoelectric effect in the
neighbourhood of the emitter-base junction acts as base current, which is amplified.
3.1.4
photothyristor photocoupler
photocoupler whose photosensitive element is a photothyristor
Note 1 to entry: Photothyristor is a thyristor that is designed to be triggered by optical radiation.
Note 2 to entry: Gate terminal may or may not be provided.

IEC 60747-5-5:2020 © IEC 2020 – 9 –
3.1.5
phototriac output photocoupler
photocoupler whose photosensitive element is a phototriac and photocoupler whose
photosensitive element is a phototriac and output is triac
Note 1 to entry: A phototriac is a triac that is designed to be triggered by optical radiation.
3.1.6
IC photocoupler
photocoupler whose photosensitive element is a photodiode/phototransistor and an integrated
circuit
3.1.7
FET photocoupler
photocoupler with one or more field-effect transistors (FETs) in the output stage
Note 1 to entry: A FET is activated by photoemitter by direct optical radiation from a photoemitter.
3.1.8
photodiode photocoupler
photocoupler whose photosensitive element is a photodiode or photodiode array
3.1.9
IC input photocoupler
photocoupler whose input element consists of an integrated circuit and a photoemitter
3.1.10
solid state opto-relay
photocoupler whose output switches digitally without requiring a supply voltage
Note 1 to entry: The term "solid state opto-relay" includes photorelay, photothyristor photocoupler, phototriac
photocoupler and FET/IGBT photocoupler.
3.1.11
current transfer ratio
H
f(ctr)
ratio of the DC output current to the DC input current, the output voltage being held constant
Note 1 to entry: The abbreviated term CTR (DC) is sometimes used instead of a symbol.
3.1.12
small-signal short-circuit forward current transfer ratio

h
f(ctr)
ratio of the AC output current to the AC input current, the output being short-circuited to AC
Note 1 to entry: The abbreviated term CTR (AC) is sometimes used instead of a symbol.
3.2
cut-off frequency
f
co
frequency at which the modulus of the small-signal current transfer ratio has decreased to
1 2 of its low-frequency value
3.3
input-to-output capacitance
C
IO
total capacitance between all input terminals or pins connected together and all output
terminals or pins connected together

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3.4
isolation resistance
R
IO
resistance between all input terminals or pins connected together and all output terminals or
pins connected together
3.4.1
repetitive peak off-state voltage for phototriac output and/or solid state opto-relay with
triac output
V
DRM
maximum applicable repetitive peak reverse voltage between anode and cathode in off-state
under specified gate conditions
3.4.2
peak off-state current
I
DRM
forward leakage current between the off-state output terminals under specified conditions
3.4.3
peak on-state voltage
V
TM
peak forward voltage between on-state output terminals under specified conditions
3.4.4
DC off-state current
I
BD
forward leakage current between off-state output terminals under specified conditions
3.4.5
DC on-state voltage
V
T
DC forward voltage between on-state output terminals under specified conditions, when the
specified forward current is applied between on-state output terminals
3.4.6
holding current
I
H
minimum on-state current in output to maintain the on-state under specified conditions
3.4.7
critical rate of rise of off-state voltage
dV/dt
rate of rise of off-state voltage just before the transition from off-state to on-state under the
specified operating conditions
3.4.8
trigger input current
I
FT
minimum input forward current to switch from off-state to on-state in output under specified
conditions
3.5
common mode transient immunity
CMTI
maximum tolerable rate of rise (or fall) of a common mode voltage (V ), the specification of
CM
which should include the amplitude of the common mode pulse (V ), which is applied across
CM
the two grounds of the photocoupler and should not exceed the maximum rated transient

isolation voltage specification of the photocoupler as defined by the V
IOTM
IEC 60747-5-5:2020 © IEC 2020 – 11 –
3.6
photocoupler providing protection against electric shock
photocoupler which has been subjected to operating conditions (safety ratings) that exceed
the specified ratings (limiting values) for normal operation
3.6.1
safety rating
˂of a photocoupler˃ electrical, thermal, and mechanical operating conditions that exceed the
specified ratings for reinforced isolation (limiting values) for normal operation, and to which
the specified safety requirements refer
3.6.2
electrical safety requirement
˂of a photocoupler˃ electrical requirements for reinforced or double insulation that have to be
met and maintained after the photocoupler has been subjected to specified safety ratings, to
ensure protection against electrical shock
Note 1 to entry: The photocoupler may become permanently inoperative when safety ratings are applied.
Note 2 to entry: For the definition of double and reinforced insulation, see 3.17.4 and 3.17.5 of IEC 60664-1:2007.
3.6.3
partial discharge
p
d
localized electrical discharge which occurs in the insulation between input and output
terminals of the photocoupler
Note 1 to entry: For the technical details of partial discharge, see 3.1 of IEC 60270:2000.
3.6.4
apparent charge
q
electrical charge caused by a partial discharge in the photocoupler
3.6.5
threshold apparent charge
q
TH
specified value of apparent charge that is as small as technically feasible and to which
measured values of the partial-discharge inception voltage or extinction voltage, respectively,
refer
Note 1 to entry: A threshold apparent charge of 5 pC was found to be a practicable criterion for a photocoupler.
Otherwise it should be defined on each individual device design. Smaller values are desirable but are not viable at
this time.
Note 2 to entry: In actual tests, this criterion applies to the apparent charge pulse with the maximum value.
Note 3 to entry: The term "specified discharge magnitude" (see 3.18.2 of IEC 60664-1:2007) is synonymous with
"threshold apparent charge".
3.6.6
partial discharge test voltage
V
m
isolation voltage applied during the partial discharge test period
Note 1 to entry: Figure 1 and Figure 2 illustrate the related terms and letter symbols for methods a and b
respectively.
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t initial time (method a) only)

ini
t (partial-discharge) stress time
st
t (partial-discharge) measuring time
m
t , t , t , t settling times
1 2 3 4
Figure 1 – Time intervals for method a)

IEC 60747-5-5:2020 © IEC 2020 – 13 –

Method b1)
Method b2)
Method b3)
t isolation test time (method b) only) t isolation test stress time (method b) only)
ini,b st1
t (partial-discharge) stress time t (partial-discharge) measuring time
st2 m
t , t , t , t settling times
1 2 3 4
Figure 2 – Time intervals for method b)

– 14 – IEC 60747-5-5:2020 © IEC 2020
Note 2 to entry: Specified values of this voltage may be expressed as a multiple of the specified value of the
maximum working isolation voltage or maximum repetitive peak isolation voltage: V = F × V if V ≥ V .
m IOWM IOWM IORM
(V = F × V or V = F × V , whichever is higher. Refer to 3.6.7 c) for multiplying factor.
m IOWM m IORM
Note 3 to entry: Test voltage, where the apparent charge has to be equal or less than the specified value.
3.6.7
initial test voltage
V
ini
test voltage applied during the initial test time t
ini
Note 1 to entry:
a) Initial voltage method a; V , see Table F.1 of IEC 60664-1:2007 for minimum voltages; interpolation is also
ini,a
possible). The value of the voltage applied at the beginning of the measurement, for a specified time t , which
ini
is intended to simulate the occurrence of a transient overvoltage.
b) Initial test voltage method b; V , the isolation test voltage applied between the short-circuited input and the
ini,b
short-circuited output terminals at routine test (method b). A withstand voltage equal to the manufacturer's
rating with a maximum of V .
IOTM
c) Multiplying factor: F in accordance with IEC 60664-1:2007, 6.1.3.5.1,
at routine test stage: F = 1,875;
at sample test stage and after the life tests, subgroup 1: F = 1,6;
after endurance tests, subgroups 2 and 3: F = 1,2
Note 2 to entry: The initial test voltage is higher than or equal to the test voltage in the second part of the test
period in which partial discharge characteristics are measured, see 3.6.6.
Note 3 to entry: For method a), the specified value for the initial test voltage is equal to the specified value of the
maximum transient isolation voltage V .
IOTM
Note 4 to entry: For method b), the specified value for the initial test voltage (isolation voltage) is equal to or
lower than the specified value of the maximum transient isolation voltage V .
IOTM
Note 5 to entry: The equivalent RMS value of the AC test voltage may also be used.
3.6.8
partial-discharge inception voltage
V
i
lowest peak value of the AC test voltage at which the apparent charge is greater than the
specified threshold apparent charge, if the test voltage is increased from a lower value where
no partial discharge occurs
Note 1 to entry: The equivalent RMS value of the AC test voltage may also be used.
3.6.9
partial-discharge extinction voltage
V
e
lowest peak value of the AC test voltage at which the apparent charge is smaller than the
specified threshold apparent charge, if the test voltage is reduced from a higher value where
such discharge occurs
Note 1 to entry: The equivalent RMS value of the AC test voltage may also be used.
3.6.10
maximum working isolation voltage
V
IOWM
RMS value of withstand voltage assigned by the manufacturer of the photocoupler,
characterizing the specified (long term or the working voltage) withstand capability of its
reinforced isolation
Note 1 to entry: The RMS voltage includes equivalent DC voltage.

IEC 60747-5-5:2020 © IEC 2020 – 15 –
3.6.11
maximum surge isolation voltage
V
IOSM
highest instantaneous value of an isolation voltage pulse of specified wave shape with short
time duration, pulses of both polarities
Note 1 to entry: See Figure 3 for details on the test voltage.

Figure 3 – Test voltage
3.6.12
DC isolation voltage
V
IO
value of the constant isolation voltage
3.6.13
repetitive peak isolation voltage
V
IORM
highest instantaneous value of the isolation voltage including all repetitive transient voltages,
but excluding all non-repetitive transient voltages
Note 1 to entry: It is implied that this is a reinforced rating.
Note 2 to entry: A repetitive transient voltage is usually a function of the circuit. A non-repetitive transient voltage
is usually due to an external cause and it is assumed that its effect has completely disappeared before the next
non-repetitive voltage transient arrives.
3.6.14
maximum transient isolation voltage
V
IOTM
value of impulse withstand voltage assigned by the manufacturer of the photocoupler
characterizing the specified withstand capability of its isolation against transient overvoltage
3.6.15
maximum withstanding isolation voltage
V
ISO
maximum withstanding isolation AC (RMS) voltage for 1 min
Note 1 to entry: The RMS voltage includes equivalent DC voltage. maximum transient isolation voltage.

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3.7 Symbols for limiting values (absolute maximum system) over the operating
temperature range, unless otherwise stated
T minimum storage temperature
stg min
T maximum storage temperature
stg max
T minimum or maximum ambient operating temperature
amb
T minimum or maximum reference-point operating temperature
ref
T maximum soldering temperature
sld
V maximum continuous reverse input voltage
R
V maximum collector-base voltage
CBO
I maximum continuous collector current
C
I maximum continuous forward input current
F
I maximum peak forward input current
FM
P maximum power dissipation
max
P maximum total power dissipation of the package
tot
4 Electrical characteristics
4.1 Phototransistor output photocoupler
See Table 1 for the electrical characteristics of the phototransistor output photocoupler.
Table 1 – Phototransistor electrical characteristics
Characteristics Conditions at Notes Symbols Requirements
T or T = 25 °C,
amb case
unless otherwise stated
4.1.1 Input diode forward I specified V Max.
F F
voltage
4.1.2 Input diode reverse V specified I Max.
R R
current
4.1.3 Collector-emitter dark V specified, I = 0,  I Max.
CE F CEO
current
I = 0 (base open-circuit)
B
or, where appropriate*, V specified, I = 0,  I Max.
CB F CBO
collector-base dark
I = 0
E
current
Collector-emitter dark V specified, I = 0,
4.1.4 I Max.
CE F CEO
current
I = 0, T or T
B amb ref
specified
or, where appropriate*, V specified, I = 0,  I Max.
CB F CBO
collector-base dark
I = 0
E
current
T or T specified
amb ref
4.1.5 Collector-emitter I and I specified, I = 0 V Max.
F C B CE(sat)
saturation voltage
or, where appropriate*, I and I specified, I = 0 V
Max.
F C B CB
collector-base voltage
4.1.6 Current transfer ratio I or I and V specified, h or Min. Max.
F C CE F
I = 0 CTR (DC)
B
4.1.7 Where appropriate, I or I and V specified, h or
Min. Max.
F C CE f
differential current
I = 0, frequency specified CTR (AC)
B
transfer ratio
IEC 60747-5-5:2020 © IEC 2020 – 17 –
Characteristics Conditions at Notes Symbols Requirements
T or T = 25 °C,
case
amb
unless otherwise stated
4.1.8 Isolation resistance V specified 1 R Min.
IO IO
between input and output
4.1.9 Where appropriate, input- f = 1 MHz, I = 0, I = 0 1 C Max.
IO
F C
to-output capacitance
4.1.10 Where appropriate, Specified V , I and R ,
CC F L
switching times: t Max.
and nominal I , test circuit on
C
turn-on time and Max.
t
specified off
turn-off time
or: Specified V , I and R ,
CC F L
rise time and t Max.
and nominal I , test circuit r
C
fall time Max.
t
specified f
4.1.11 Where appropriate, cut-off I or I and V specified, 2 F Min.
F C CE co
frequency
I = 0
B
* For operation in the diode mode.
All input terminals should be connected together and all output terminals should be connected together.
NOTE The cut-off frequency is the lowest frequency at which the magnitude of the AC current transfer rat
...