IEC 61188-7:2009
(Main)Printed boards and printed board assemblies - Design and use - Part 7: Electronic component zero orientation for CAD library construction
Printed boards and printed board assemblies - Design and use - Part 7: Electronic component zero orientation for CAD library construction
IEC 61188-7:2009 establishes a consistent technique for the description of electronic component orientation, and their land pattern geometries. This facilitates and encourages a common data capture and transfer methodology amongst and between global trading partners.
Cartes imprimées et cartes imprimées équipées - Conception et utilisation - Partie 7: Orientation nulle des composants électroniques pour l'élaboration de la bibliothèque CAO
La CEI 61188-7:2009 établit une technique cohérente pour décrire l'orientation des composants électroniques, ainsi que les géométries de leurs zones de report. Cela facilite et encourage une méthodologie commune de saisie et de transfert des données parmi et entre les partenaires commerciaux mondiaux.
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IEC 61188-7
®
Edition 1.0 2009-05
INTERNATIONAL
STANDARD
Printed boards and printed board assemblies – Design and use –
Part 7: Electronic component zero orientation for CAD library construction
IEC 61188-7:2009(E)
---------------------- Page: 1 ----------------------
THIS PUBLICATION IS COPYRIGHT PROTECTED
Copyright © 2009 IEC, Geneva, Switzerland
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: inmail@iec.ch
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: csc@iec.ch
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Fax: +41 22 919 03 00
---------------------- Page: 2 ----------------------
IEC 61188-7
®
Edition 1.0 2009-05
INTERNATIONAL
STANDARD
Printed boards and printed board assemblies – Design and use –
Part 7: Electronic component zero orientation for CAD library construction
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
R
ICS 31.180 ISBN 978-2-88910-437-6
® Registered trademark of the International Electrotechnical Commission
---------------------- Page: 3 ----------------------
– 2 – 61188-7 © IEC:2009(E)
CONTENTS
FOREWORD.3
INTRODUCTION.5
1 Scope.6
2 Normative references .6
3 Basic rules .6
3.1 Common rules .6
3.2 General basic rules .7
3.3 Level A basic rule.7
3.4 Level B basic rules .7
3.5 File description definition.7
3.6 Component orientations .8
4 Origin point of land-pattern .16
4.1 General .16
4.2 Surface mount components .16
4.3 Through-hole leaded components.17
5 Land pattern to foot print comparison .18
6 Components with one terminal.18
6.1 Surface mount components .18
6.2 Through-hole leaded components.18
Figure 1 – Example of Level A orientation concepts.8
Figure 2 – Connector and switch library symbol examples .17
Figure 3 – Through-hole components with terminal point of origin orientation .17
Figure 4 – Circular or square one terminal component .18
Figure 5 – Rectangular or oval one terminal component.18
Figure 6 – Surface mount components with one lead offset.18
Table 1 – Discrete component land pattern conventions .9
Table 2 – Diode and transistor land pattern conventions .10
Table 3 – Transistor and IC land pattern conventions .11
Table 4 – Integrated circuit packages land pattern conventions .12
Table 5 – Integrated circuit packages land pattern conventions .13
Table 6 – BGA land pattern conventions .14
Table 7 – Resistor array and connector land pattern conventions .15
Table 8 – Level A land pattern convention summary .15
Table 9 – Level B land pattern convention summary .16
---------------------- Page: 4 ----------------------
61188-7 © IEC:2009(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PRINTED BOARDS AND PRINTED BOARD ASSEMBLIES –
DESIGN AND USE –
Part 7: Electronic component zero orientation
for CAD library construction
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 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 61188-7 has been prepared by IEC technical committee 91:
Electronics assembly technology.
The text of this standard is based on the following documents:
FDIS Report on voting
91/854/FDIS 91/866/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.
---------------------- Page: 5 ----------------------
– 4 – 61188-7 © IEC:2009(E)
A list of all parts of the IEC 61188 series, under the general title Printed boards and printed
board assemblies – Design and use, 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 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.
The contents of the corrigendum of July 2009 have been included in this copy.
---------------------- Page: 6 ----------------------
61188-7 © IEC:2009(E) – 5 –
INTRODUCTION
One of the factors of establishing a CAD library component description and land pattern
standard is to adopt a fixed zero component orientation so that all CAD images are built with
the same rotation for the purpose of assembly machine automation.
The land pattern standards clearly define all the properties necessary for standardization and
acceptability of a one world CAD library. The main objective in defining a one world CAD
library is to achieve the highest level of electronic product development automation. This
encompasses all the processes involved from engineering to PCB layout to fabrication,
assembly and test. The data format standards need this type of consistency in order to meet
the efficiency that electronic data transfer can bring to the industry.
Many large firms have spent millions of dollars creating and implementing their own unique
standards for their own electronic product development automation. These standards are
proprietary to each firm and are not openly shared with the rest of the industry. This has
resulted in massive duplication of effort costing the industry millions of man hours in waste
and creating industry chaos and global non-standardization.
The industry associations responsible for component descriptions and tape and reel
orientation have tried valiantly to influence the industry by making good standards that
describe the component outlines and how they should be positioned in the delivery system to
the equipment on the manufacturing floor. Suppliers of parts have either not adhered to the
recommendations or have misunderstood the intent and provided their products in different
orientations.
The Land pattern standards (IEC 61188-5-1, IEC 61188-5-2, IEC 61188-5-3, IEC 61188-5-4,
IEC 61188-5-5, IEC 61188-5-6 and IEC 61188-5-8) put an end to the proprietary intellectual
property and introduce a world standard so every electronics firm can benefit from electronic
product development automation. The data format standards (IPC-2581 and IEC 61182-2) are
an open database XML software code that is neutral to all the various CAD ASCII formats. For
true machine automation to exist, the world desperately needs a neutral CAD database format
that all PCB manufacturing machines can read.
The main purpose of creating the land pattern standards is to achieve reliable solder joint
formation platforms; the reason for developing the data transfer structure is to improve the
efficiency with which engineering intelligence is converted to manufacturing reality. Even if the
neutral CAD format can drive all the manufacturing machines, it would be meaningless unless
the component description standard for CAD land patterns was implemented with some
consistency. Zero component orientation has a key role in machine automation.
The obvious choice for global standardization for EE hardware engineering, PCB design
layout, manufacturing, assembly and testing processes is to incorporate the standard land
pattern conventions. Any other option continues the confusion and additional manual hours of
intervention in order to achieve the goals of automation. In addition, the ease of having one
system export a file so that another system can accomplish the work may require
unnecessary manipulation of the neutral format in order to meet the object of clear,
unambiguous software code.
The design of any assembly will continue to permit arrangement and orientation of
components at any orientation consistent with design standards. Starting from a commonly
understood data capture concept will benefit the entire supply chain.
This standard defines angle and origin point of land-pattern for land-pattern designing.
---------------------- Page: 7 ----------------------
– 6 – 61188-7 © IEC:2009(E)
PRINTED BOARDS AND PRINTED BOARD ASSEMBLIES –
DESIGN AND USE –
Part 7: Electronic component zero orientation
for CAD library construction
1 Scope
This part of IEC 61188 establishes a consistent technique for the description of electronic
component orientation, and their land pattern geometries. This facilitates and encourages a
common data capture and transfer methodology amongst and between global trading
partners.
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 61182-2, Printed board assembly products – Manufacturing description data and
transfer methodology – Part 2: Generic requirements
IEC 61188-5-1, Printed boards and printed board assemblies – Design and use – Part 5-1:
Attachment (land/joint) considerations – Generic requirements
IEC 61188-5-2, Printed boards and printed board assemblies – Design and use – Part 5-2:
Attachment (land/joint) considerations – Discrete components
IEC 61188-5-3, Printed boards and printed board assemblies – Design and use – Part 5-3:
Attachment (land/joint) considerations – Components with gull-wing leads on two sides
IEC 61188-5-4, Printed boards and printed board assemblies – Design and use – Part 5-4:
Attachment (land/joint) considerations – Components with J-leads on two sides
IEC 61188-5-5, Printed boards and printed board assemblies – Design and use – Part 5-5:
Attachment (land/joint) considerations – Components with gull-wing leads on four sides
IEC 61188-5-6, Printed boards and printed board assemblies – Design and use – Part 5-6:
Attachment (land/joint) consid
...
IEC 61188-7
®
Edition 1.0 2009-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Printed boards and printed board assemblies – Design and use –
Part 7: Electronic component zero orientation for CAD library construction
Cartes imprimées et cartes imprimées équipées – Conception et utilisation –
Partie 7: Orientation nulle des composants électroniques pour l’élaboration
d’une bibliothèque CAO
IEC 61188-7:2009
---------------------- Page: 1 ----------------------
THIS PUBLICATION IS COPYRIGHT PROTECTED
Copyright © 2009 IEC, Geneva, Switzerland
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: inmail@iec.ch
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: csc@iec.ch
Tel.: +41 22 919 02 11
Fax: +41 22 919 03 00
A propos de la CEI
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normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.
A propos des publications CEI
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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.
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Service clients ou contactez-nous:
Email: csc@iec.ch
Tél.: +41 22 919 02 11
Fax: +41 22 919 03 00
---------------------- Page: 2 ----------------------
IEC 61188-7
®
Edition 1.0 2009-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Printed boards and printed board assemblies – Design and use –
Part 7: Electronic component zero orientation for CAD library construction
Cartes imprimées et cartes imprimées équipées – Conception et utilisation –
Partie 7: Orientation nulle des composants électroniques pour l’élaboration
d’une bibliothèque CAO
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
R
CODE PRIX
ICS 31.180 ISBN 978-2-88910-438-3
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 3 ----------------------
– 2 – 61188-7 © IEC:2009
CONTENTS
FOREWORD.3
INTRODUCTION.5
1 Scope.6
2 Normative references .6
3 Basic rules .6
3.1 Common rules .6
3.2 General basic rules .7
3.3 Level A basic rule.7
3.4 Level B basic rules .7
3.5 File description definition.7
3.6 Component orientations .8
4 Origin point of land-pattern .16
4.1 General .16
4.2 Surface mount components .16
4.3 Through-hole leaded components.17
5 Land pattern to foot print comparison .18
6 Components with one terminal.18
6.1 Surface mount components .18
6.2 Through-hole leaded components.18
Figure 1 – Example of Level A orientation concepts.8
Figure 2 – Connector and switch library symbol examples .17
Figure 3 – Through-hole components with terminal point of origin orientation .17
Figure 4 – Circular or square one terminal component .18
Figure 5 – Rectangular or oval one terminal component.18
Figure 6 – Surface mount components with one lead offset.18
Table 1 – Discrete component land pattern conventions .9
Table 2 – Diode and transistor land pattern conventions .10
Table 3 – Transistor and IC land pattern conventions .11
Table 4 – Integrated circuit packages land pattern conventions .12
Table 5 – Integrated circuit packages land pattern conventions .13
Table 6 – BGA land pattern conventions .14
Table 7 – Resistor array and connector land pattern conventions .15
Table 8 – Level A land pattern convention summary .15
Table 9 – Level B land pattern convention summary .16
---------------------- Page: 4 ----------------------
61188-7 © IEC:2009 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PRINTED BOARDS AND PRINTED BOARD ASSEMBLIES –
DESIGN AND USE –
Part 7: Electronic component zero orientation
for CAD library construction
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 61188-7 has been prepared by IEC technical committee 91:
Electronics assembly technology.
This bilingual version, published in 2009-10 corresponds to the English version.
The text of this standard is based on the following documents:
FDIS Report on voting
91/854/FDIS 91/866/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.
---------------------- Page: 5 ----------------------
– 4 – 61188-7 © IEC:2009
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.
A list of all parts of the IEC 61188 series, under the general title Printed boards and printed
board assemblies – Design and use, 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 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.
The contents of the corrigendum of July 2009 have been included in this copy.
IMPORTANT – The “colour inside” logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this publication using a colour printer.
---------------------- Page: 6 ----------------------
61188-7 © IEC:2009 – 5 –
INTRODUCTION
One of the factors of establishing a CAD library component description and land pattern
standard is to adopt a fixed zero component orientation so that all CAD images are built with
the same rotation for the purpose of assembly machine automation.
The land pattern standards clearly define all the properties necessary for standardization and
acceptability of a one world CAD library. The main objective in defining a one world CAD
library is to achieve the highest level of electronic product development automation. This
encompasses all the processes involved from engineering to PCB layout to fabrication,
assembly and test. The data format standards need this type of consistency in order to meet
the efficiency that electronic data transfer can bring to the industry.
Many large firms have spent millions of dollars creating and implementing their own unique
standards for their own electronic product development automation. These standards are
proprietary to each firm and are not openly shared with the rest of the industry. This has
resulted in massive duplication of effort costing the industry millions of man hours in waste
and creating industry chaos and global non-standardization.
The industry associations responsible for component descriptions and tape and reel
orientation have tried valiantly to influence the industry by making good standards that
describe the component outlines and how they should be positioned in the delivery system to
the equipment on the manufacturing floor. Suppliers of parts have either not adhered to the
recommendations or have misunderstood the intent and provided their products in different
orientations.
The Land pattern standards (IEC 61188-5-1, IEC 61188-5-2, IEC 61188-5-3, IEC 61188-5-4,
IEC 61188-5-5, IEC 61188-5-6 and IEC 61188-5-8) put an end to the proprietary intellectual
property and introduce a world standard so every electronics firm can benefit from electronic
product development automation. The data format standards (IPC-2581 and IEC 61182-2) are
an open database XML software code that is neutral to all the various CAD ASCII formats. For
true machine automation to exist, the world desperately needs a neutral CAD database format
that all PCB manufacturing machines can read.
The main purpose of creating the land pattern standards is to achieve reliable solder joint
formation platforms; the reason for developing the data transfer structure is to improve the
efficiency with which engineering intelligence is converted to manufacturing reality. Even if the
neutral CAD format can drive all the manufacturing machines, it would be meaningless unless
the component description standard for CAD land patterns was implemented with some
consistency. Zero component orientation has a key role in machine automation.
The obvious choice for global standardization for EE hardware engineering, PCB design
layout, manufacturing, assembly and testing processes is to incorporate the standard land
pattern conventions. Any other option continues the confusion and additional manual hours of
intervention in order to achieve the goals of automation. In addition, the ease of having one
system export a file so that another system can accomplish the work may require
unnecessary manipulation of the neutral format in order to meet the object of clear,
unambiguous software code.
The design of any assembly will continue to permit arrangement and orientation of
components at any orientation consistent with design standards. Starting from a commonly
understood data capture concept will benefit the entire supply chain.
This standard defines angle and origin point of land-pattern for land-pattern designing.
---------------------- Page: 7 ----------------------
– 6 – 61188-7 © IEC:2009
PRINTED BOARDS AND PRINTED BOARD ASSEMBLIES –
DESIGN AND USE –
Part 7: Electronic component zero orientation
for CAD library construction
1 Scope
This part of IEC 61188 establishes a consistent technique for the description of electronic
component orientation, and their land pattern geometries. This facilitates and encourages a
common data capture and transfer methodology amongst and between global trading
partners.
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 61182-2, Printed board assembly products – Manufacturing description data and
transfer methodology – Part 2: Generic requirements (available in English only)
IEC 61188-5-1, Printed boards and printed board assemblies – Design and use – Part 5-1:
Attachment (land/joint) considerations – Generic requirements
IEC 61188-5-2, Printed boards and printed board assemblies – Design and use – Part 5-2:
Attachment (land/joint) considerations – Discrete components
IEC 61188-5-3, Printed boards and printed board assemblies – Design and use – Part 5-3:
Attachment (land/joint) considerations – Components with gull-wing leads on two sides
IEC 61188-5-4, Printed boards and printed board assemblies – Design and use – Part 5-4:
Attachment (land/joint) considerations – Components with J-leads on two sides
IEC 61188-5-5, Printed boards and printed board assemblies – Design and use – Part 5-5:
Attachment (land/joint) considerations – Components with gull-wing leads on four sides
IEC 61188-5-6, Printed boards and printed board assemblies – Design and use – Part 5-6:
Attachment (land/joint) considerations – Chip carriers with J-leads on four sides
IEC 61188-5-8, Printed boards and printed board assemblies – Design and use – Part 5-8:
Attachment (land/joint) considerations – Area array components (BGA, FBGA, CGA, LGA)
(available in English only)
3 Basic rules
3.1 Common rules
Common rules are divided into two groups; level A and level B. The main difference between
the rules is the original orientation within the CAD system library. This orientation may be any
version that the designers finds useful including his own version, however when the
information is transferred to an assembler the orientation shall be properly defined without
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ambiguity or shall be corrected in order that any variation between the different systems are
properly matched. This conversion of the CAD data to manufacturing information may include
the datum of the board, fabrication panel or assembly array panel and will have the proper
orientation of all components on the board no matter what library was used as the original
input.
3.2 General basic rules
The following basic rules apply.
• Components and land-patterns are drawn in top view.
• The component point of origin is shown by + or x.
• The origin point of land-patterns may be different from the origin point of the placement.
• A circumscribing rectangle which contains the component body and land patterns (in top
view) should be a part of the library component description. This rectangle is the courtyard
that provides a minimum electrical and physical clearance for the part and the land
pattern. The point of origin of the description should match that of the component and land
pattern.
• The arrangement of land-patterns is fixed uniformly by the classification and the shape of
components and is described in IEC 61188-5-1 through IEC 61188-5-8. The information
for the land-patterns is independent from the angle in the component delivery system
(tape, tray, tube etc.). The location of pin one in the land pattern or component description
shall be identical with any polarization mark on the component. If other descriptions are
used on the component data, (e.g., cathode, anode, base, emitter, collector, etc.) the
library description shall assign an appropriate pin one designation.
• The component orientation shall position pin one as being on the left hand side of the
component description.
• The component, land pattern and circumscribing rectangle descriptions, shall be identical
in the computer library with each description using the same point of origin coordinates. It
is recommended that the point of origin is the same as the way the component is
positioned on the final design of the board which is normally by the centroid of the
component body. Only the component rotation shall be altered to match the rules for level
A or level B descriptions for components with more than two pins.
3.3 Level A basic rule
For level A the following basic rule applies.
• For level A type component descriptions for multiple leaded parts, pin one shall be left
oriented as indicated in the basic rules, however, pin one shall be located at the upper or
upper-left position.
3.4 Level B basic rules
For level B the following basic rule applies.
• For level B type component descriptions for multiple leaded parts, pin one shall be left
oriented per the basic rules however, pin one shall be located at the left or lower-left
position.
3.5 File description definition
Since the basic rules allow two variations of levels in the description of the CAD system
library, it is a mandatory requirement to define which level was used (level A or Level B) for
the component descriptions in the data file. This information is a mandatory requirement in
the Header of any file that incorporates land patterns using these principles of zero-based
orientation. See Figure 1.
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Initial
primitive
0° orientation
Rotate counterclockwise
Mirror image
90° orientation
Rotate counterclockwise
Mirror image
180° orientation
Rotate counterclockwise
Mirror image
270° orientation
IEC 832/09
Figure 1 – Example of Level A orientation concepts
3.6 Component orientations
The zero component orientations expressed in this standard are defined in terms of the
standard component CAD library with respect to a given PCB design. Recognizing that a
single land pattern may be used for the same component part from different suppliers and that
each component supplier may have different orientations on their reels or that the
components may come in trays, there exists the possibility that the PCB designer loses the
ability to reference a single land pattern if the zero rotation of a part is according to the
method the component is delivered to the assembly machine.
Since the CAD library contains a single land pattern, the zero component rotation is thus
defined according to the CAD library. Subsequently, component suppliers can identify the
orientation of the parts on the reels by associating the placement of the part on the reel to
zero orientations defined in IEC 61188-7. If pin 1 is at the lower left as defined by the pick and
place machine tape and reel, for example, then the component on the reel is rotated 90°
counterclockwise from the zero rotation given in IEC 61188-7. Standardizing the orientation of
components for the installation and utilization of various packaging methods, such as tubes,
trays or tapes and reels, among the variations of automated assembly equipment existing
today is outside the scope of this document.
Table 1 through Table 7 show zero component rotations using the basic rules and rules for
level A and level B component descriptions.
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Table 1 – Discrete component land pattern conventions
Package type Component example Level A Level B
Chip capacitor
Chip resistor
Chip inductor
Molded capacitor
Molded diode
Molded inductor
Precision
wirewound
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Table 2 – Diode and transistor land pattern conventions
Package type Component example Level A Level B
Diode (MELF)
Resistor (MELF)
Aluminum
electrolytic
capacitor
SOT23-3
SOT23-5
SOT343
SOT223
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Table 3 – Transistor and IC land pattern conventions
Package type Component example Level A Level B
TO252 (DPAK)
SOIC, SOP, and
SSOP
TSSOP
SOJ
Square QFP
Pin 1 in corner
Rectangular QFP
Pin 1 in corner
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Table 4 – Integrated circuit packages land pattern conventions
Package Component Example Level A Level B
Type
Bump QFP
Pin 1 in
corner
Bump QFP
Pin 1 in
middle
Ceramic flat
package
CQFP
(ceramic
quad flat
package)
PLCC (QFJ)
square
J leaded
Pin 1 in
middle
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61188-7 © IEC:2009 – 13 –
Table 5 – Integrated circuit packages land pattern conventions
Package Component Example Level A Level B
Type
PLCC (QFJ)
rectangular
J leaded
Pin 1 in
middle
LCC square
Pin 1 in
middle
QFN square
QFN
rectangular
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Table 6 – BGA land pattern conventions
Package Component example Level A Level B
type
BGA
square
Numeric designations
for horizontal grid
4 3 2 1
b
BGA
A
REF
Alpha
rectangular
B
designations
C
D for vertical grid
(letters I, O, Q
and S not used)
TYP
-s-
c
TYP
-s-
REF
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Table 7 – Resistor array and connector land pattern conventions
Package Component example Level A Level B
type
Resistor
array
SMT
Pin 1
connector
Pin 1
Table 8 provides a summary of the land pattern conventions for level A library concepts.
Table 8 – Level A land pattern convention summary
Level A summary – Component marking identifies pin 1 of land pattern
1) Chip capacitors, resistors and inductors (RES, CAP and IND) – Pin 1 of land pattern on left
2) Molded Inductors (INDM), resistors (RESM) and tantalum capacitors (CAPT) – Pin 1 of land pattern on left
3) Precision wire-wound Inductors (INDP) – Pin 1 of land pattern on left
4) MELF diodes – Pin 1 of land pattern on left
5) Aluminum electrolytic capacitors (CAPAE) – Pin 1 of land pattern on left
6) SOT Devices (SOT23, SOT23-5, SOT223, SOT89, SOT143, etc.) – Pin 1 of land pattern on upper left
7) TO252 & TO263 (DPAK Type) devices – Pin 1 of land pattern on up
...
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