IEC 62024-2:2008

High frequency inductive components - Electrical characteristics and measuring methods - Part 2: Rated current of inductors for DC to DC converters

IEC 62024-2:2008 specifies the measuring methods of the rated direct current limits for small inductors. Standardized measuring methods for the determination of ratings enable users to accurately compare the current ratings given in various manufacturers' data books. This standard is applicable to leaded and surface mount inductors with dimensions according to IEC 62025-1 and generally with rated current less than 22 A, although inductors with rated current greater than 22 A are available that fall within the dimension restrictions of this standard (no larger than 12 mm x 12 mm footprint approximately). These inductors are typically used in DC to DC converters built on PCB, for electric and telecommunication equipment, and small size switching power supply units. The measuring methods are defined by the saturation and temperature rise limitations induced solely by direct current.

Composants inductifs à haute fréquence - Caractéristiques électriques et méthodes de mesure - Partie 2: Courant assigné des bobines d'induction pour des convertisseurs continus-continus

La CEI 62024-2:2008 spécifie les méthodes de mesure des limites de courant continu assigné pour de petites bobines d'induction. Les méthodes de mesure normalisées pour la détermination des valeurs nominales permettent aux utilisateurs de comparer précisément les valeurs nominales courantes figurant dans les différents recueils de données fabricants. La présente norme s'applique aux bobines d'induction à sorties et pour montage en surface dont les dimensions sont conformes à la CEI 62025-1 et dont généralement le courant assigné est inférieur à 22 A, même si des bobines d'induction de courant assigné supérieur à 22 A sont disponibles et s'intègrent dans les restrictions de dimensions de cette norme (empreinte ne dépassant pas 12 mm x 12 mm, approximativement). Ces bobines d'induction sont typiquement utilisées dans des convertisseurs continus-continus montés sur des cartes à circuit imprimé (CCI), pour des matériels électriques et de télécommunications, ainsi que pour des unités d'alimentation de puissance de commutation de petite taille. Les méthodes de mesure sont définies par les limites de saturation et d'échauffement induites uniquement par le courant continu.

General Information

• Status: Published
• Publication Date: 07-Oct-2008
• ICS: 29.100.10 - Magnetic components
• Technical Committee: TC 51 - Magnetic components, ferrite and magnetic powder materials
• Drafting Committee: WG 9 - TC 51/WG 9
• Current Stage: DELPUB - Deleted Publication
• Start Date: 28-Dec-2018
• Completion Date: 31-Mar-2020

Relations

• Revised: IEC 62024-2:2020 - High frequency inductive components - Electrical characteristics and measuring methods - Part 2: Rated current of inductors for DC-to-DC converters
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 62024-2
Edition 1.0 2008-10
INTERNATIONAL
STANDARD
High frequency inductive components – Electrical characteristics and measuring
methods –
Part 2: Rated current of inductors for DC to DC converters

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form

or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester.
If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,

please contact the address below or your local IEC member National Committee for further information.

IEC Central Office
3, rue de Varembé
CH-1211 Geneva 20
Switzerland
Email: [e-mail]
Web: 1Hwww.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.
ƒ Catalogue of IEC publications: 2Hwww.iec.ch/searchpub
The IEC on-line Catalogue enables you to search by a variety of criteria (reference number, text, technical committee,…).
It also gives information on projects, withdrawn and replaced publications.
ƒ IEC Just Published: 3Hwww.iec.ch/online_news/justpub
Stay up to date on all new IEC publications. Just Published details twice a month all new publications released. Available
on-line and also by email.
ƒ Electropedia: 4Hwww.electropedia.org
The world's leading online dictionary of electronic and electrical terms containing more than 20 000 terms and definitions
in English and French, with equivalent terms in additional languages. Also known as the International Electrotechnical
Vocabulary online.
ƒ Customer Service Centre: 5Hwww.iec.ch/webstore/custserv
If you wish to give us your feedback on this publication or need further assistance, please visit the Customer Service
Centre FAQ or contact us:
Email: [e-mail]
Tel.: [phone]
Fax: [phone]
IEC 62024-2
Edition 1.0 2008-10
INTERNATIONAL
STANDARD
High frequency inductive components – Electrical characteristics and measuring
methods –
Part 2: Rated current of inductors for DC to DC converters

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
Q
ICS 29.100.10 ISBN 978-2-88910-607-3
– 2 – 62024-2 © IEC:2008(E)
CONTENTS
FOREWORD.3

1 Scope.5

2 Normative references .5

3 Terms and definitions .5

4 Standard atmospheric conditions.6

4.1 Standard atmospheric conditions for testing .6

4.2 Reference conditions.6

5 Measuring method of DC saturation limited current.6
5.1 General .6
5.2 Test conditions.6
5.3 Measurement circuit and calculation.7
5.4 Attachment jig of inductor.8
5.5 Measuring method.8
5.6 Quality conformance inspection.8
6 Measuring method of temperature rise limited current .8
6.1 General .8
6.2 Test conditions.9
6.3 Measurement jig.9
6.3.1 Printed-wiring board method.9
6.3.2 Lead wire method .11
6.4 Measuring method and calculation .12
6.4.1 Resistance-substitution method .12
6.4.2 Thermo-couple method.13
6.5 Quality conformance inspection.14
7 Determination of rated current .14
8 Information to be given in the detail specification.14
8.1 Measuring method of DC saturation limited current .14
8.2 Measuring method of temperature rise limited current .15
Annex A (informative) Example of recommended description on product specification
sheets and catalogues .16

Figure 1 – Inductance measurement circuit under application of DC saturation

condition.
Figure 2a) – Example of printed-wiring board for SMD type .10
Figure 2b) – Example of printed-wiring board for leaded type.11
Figure 2 – Example of printed-wiring board.11
Figure 3 – Temperature rise measurement circuit by resistance substitution method.12
Figure 4 – Temperature rise measurement circuit by thermo-couple method .13

Table 1 – Width of circuits .9
Table 2 – Wire size of circuits .12

62024-2 © IEC:2008(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
HIGH FREQUENCY INDUCTIVE COMPONENTS –

ELECTRICAL CHARACTERISTICS AND MEASURING METHODS –

Part 2: Rated current of inductors for DC to DC converters

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
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 62024-2 has been prepared IEC technical committee 51: Magnetic
components and ferrite materials.
The text of this standard is based on the following documents:
FDIS Report on voting
51/937/FDIS 51/941/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.
A list of all parts of IEC 62024 series, under the general title High frequency inductive
components – Electrical characteristics and measuring methods, can be found on the IEC
website.
– 4 – 62024-2 © IEC:2008(E)
The committee has decided that the contents of this publication will remain unchanged until

the maintenance result 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.
A bilingual version of this publication may be issued at a later date.

62024-2 © IEC:2008(E) – 5 –
HIGH FREQUENCY INDUCTIVE COMPONENTS –

ELECTRICAL CHARACTERISTICS AND MEASURING METHODS –

Part 2: Rated current of inductors for DC to DC converters

1 Scope
This part of IEC 62024 specifies the measuring methods of the rated direct current limits for
small inductors.
Standardized measuring methods for the determination of ratings enable users to accurately
compare the current ratings given in various manufacturers’ data books.
This standard is applicable to leaded and surface mount inductors with dimensions according
to IEC 62025-1 and generally with rated current less than 22 A, although inductors with rated
current greater than 22 A are available that fall within the dimension restrictions of this
standard (no larger than 12 mm × 12 mm footprint approximately). These inductors are
typically used in DC to DC converters built on PCB, for electric and telecommunication
equipment, and small size switching power supply units.
The measuring methods are defined by the saturation and temperature rise limitations
induced solely by direct current.
2 Normative references
The following referenced documents are indispensable for the application 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, Environmental testing – Part 1: General and guidance
IEC 62025-1, High frequency inductive components – Non-electrical characteristics and
measuring methods – Part 1: Fixed, surface mounted inductors for use in electronic and
telecommunication equipment
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
DC saturation limited current
allowable value of DC current for which the decrease of the inductance is within the specified
value
3.2
temperature rise limited current
allowable value of DC current for which the self-generation heat of the inductor results in
temperature rise within the specified value

– 6 – 62024-2 © IEC:2008(E)
4 Standard atmospheric conditions

4.1 Standard atmospheric conditions for testing

Standard atmospheric conditions for testing shall be as follows (see 5.3.1 of IEC 60068-1):

– temperature: 15 °C to 35 °C;

– relative humidity: 25 % to 75 %;

– air pressure: 86 kPa to 106
...

IEC 62024-2 ®
Edition 1.0 2008-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
High frequency inductive components – Electrical characteristics and measuring
methods –
Part 2: Rated current of inductors for DC to DC converters

Composants inductifs à haute fréquence – Caractéristiques électriques et
méthodes de mesure –
Partie 2: Courant assigné des bobines d’induction pour des convertisseurs
continus-continus
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by

any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either IEC or

IEC's member National Committee in the country of the requester.
If you have any questions about IEC copyright or have an enquiry about obtaining additional rights to this publication,
please contact the address below or your local IEC member National Committee for further information.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite
ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie
et les microfilms, sans l'accord écrit de la CEI ou du Comité national de la CEI du pays du demandeur.

Si vous avez des questions sur le copyright de la CEI ou si vous désirez obtenir des droits supplémentaires sur cette

publication, utilisez les coordonnées ci-après ou contactez le Comité national de la CEI de votre pays de résidence.

IEC Central Office
3, rue de Varembé
CH-1211 Geneva 20
Switzerland
Email: [e-mail]
Web: www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.
ƒ Catalogue of IEC publications: www.iec.ch/searchpub
The IEC on-line Catalogue enables you to search by a variety of criteria (reference number, text, technical committee,…).
It also gives information on projects, withdrawn and replaced publications.
ƒ IEC Just Published: www.iec.ch/online_news/justpub
Stay up to date on all new IEC publications. Just Published details twice a month all new publications released. Available
on-line and also by email.
ƒ Electropedia: www.electropedia.org
The world's leading online dictionary of electronic and electrical terms containing more than 20 000 terms and definitions
in English and French, with equivalent terms in additional languages. Also known as the International Electrotechnical
Vocabulary online.
ƒ Customer Service Centre: www.iec.ch/webstore/custserv
If you wish to give us your feedback on this publication or need further assistance, please visit the Customer Service
Centre FAQ or contact us:
Email: [e-mail]
Tel.: [phone]
Fax: [phone]
A propos de la CEI
La Commission Electrotechnique Internationale (CEI) est la première organisation mondiale qui élabore et publie des
normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.

A propos des publications CEI
Le contenu technique des publications de la CEI est constamment revu. Veuillez vous assurer que vous possédez
l’édition la plus récente, un corrigendum ou amendement peut avoir été publié.
ƒ Catalogue des publications de la CEI: www.iec.ch/searchpub/cur_fut-f.htm
Le Catalogue en-ligne de la CEI vous permet d’effectuer des recherches en utilisant différents critères (numéro de référence,
texte, comité d’études,…). Il donne aussi des informations sur les projets et les publications retirées ou remplacées.
ƒ Just Published CEI: www.iec.ch/online_news/justpub
Restez informé sur les nouvelles publications de la CEI. Just Published détaille deux fois par mois les nouvelles
publications parues. Disponible en-ligne et aussi par email.
ƒ Electropedia: www.electropedia.org
Le premier dictionnaire en ligne au monde de termes électroniques et électriques. Il contient plus de 20 000 termes et
définitions en anglais et en français, ainsi que les termes équivalents dans les langues additionnelles. Egalement appelé
Vocabulaire Electrotechnique International en ligne.
ƒ Service Clients: www.iec.ch/webstore/custserv/custserv_entry-f.htm
Si vous désirez nous donner des commentaires sur cette publication ou si vous avez des questions, visitez le FAQ du
Service clients ou contactez-nous:
Email: [e-mail]
Tél.: [phone]
Fax: [phone]
IEC 62024-2 ®
Edition 1.0 2008-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
High frequency inductive components – Electrical characteristics and measuring
methods –
Part 2: Rated current of inductors for DC to DC converters

Composants inductifs à haute fréquence – Caractéristiques électriques et
méthodes de mesure –
Partie 2: Courant assigné des bobines d’induction pour des convertisseurs
continus-continus
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
Q
CODE PRIX
ICS 29.100.10 ISBN 978-2-88910-608-0
– 2 – 62024-2 © IEC:2008
CONTENTS
FOREWORD.3

1 Scope.5

2 Normative references .5

3 Terms and definitions .5

4 Standard atmospheric conditions.6

4.1 Standard atmospheric conditions for testing .6

4.2 Reference conditions.6

5 Measuring method of DC saturation limited current.6
5.1 General .6
5.2 Test conditions.6
5.3 Measurement circuit and calculation.7
5.4 Attachment jig of inductor.8
5.5 Measuring method.8
5.6 Quality conformance inspection.8
6 Measuring method of temperature rise limited current .8
6.1 General .8
6.2 Test conditions.9
6.3 Measurement jig.9
6.3.1 Printed-wiring board method.9
6.3.2 Lead wire method .11
6.4 Measuring method and calculation .12
6.4.1 Resistance-substitution method .12
6.4.2 Thermo-couple method.13
6.5 Quality conformance inspection.14
7 Determination of rated current .14
8 Information to be given in the detail specification.14
8.1 Measuring method of DC saturation limited current .14
8.2 Measuring method of temperature rise limited current .15
Annex A (informative) Example of recommended description on product specification
sheets and catalogues .16

Figure 1 – Inductance measurement circuit under application of DC saturation

condition.
Figure 2a) – Example of printed-wiring board for SMD type .10
Figure 2b) – Example of printed-wiring board for leaded type.11
Figure 2 – Example of printed-wiring board.11
Figure 3 – Temperature rise measurement circuit by resistance substitution method.12
Figure 4 – Temperature rise measurement circuit by thermo-couple method .13

Table 1 – Width of circuits .9
Table 2 – Wire size of circuits .12

62024-2 © IEC:2008 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
HIGH FREQUENCY INDUCTIVE COMPONENTS –

ELECTRICAL CHARACTERISTICS AND MEASURING METHODS –

Part 2: Rated current of inductors for DC to DC converters

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
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 62024-2 has been prepared IEC technical committee 51: Magnetic
components and ferrite materials.
This bilingual version, published in 2009-02, corresponds to the English version.
The text of this standard is based on the following documents:
FDIS Report on voting
51/937/FDIS 51/941/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.
The French version of this standard has not been voted upon.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

– 4 – 62024-2 © IEC:2008
A list of all parts of IEC 62024 series, under the general title High frequency inductive

components – Electrical characteristics and measuring methods, can be found on the IEC

website.
The committee has decided that the contents of this publication will remain unchanged until

the maintenance result date indicated on the IEC web site un
...