IEC 61188-6-3:2024

Circuit boards and circuit board assemblies - Design and use - Part 6-3: Land pattern design - Description of land pattern for through hole components (THT)

IEC 61188-6-3:2024 specifies the requirements for lands and land pattern on circuit boards for the mounting of components with leads by soldering based on the solder joint requirements of IEC 61191-1 and IEC 61191-3.
This part of IEC 61188 specifies the requirements for soldering surfaces on circuit boards. This includes lands and land pattern for surface mounted components and also solderable hole configurations for through hole mounted components. These requirements are based on the solder joint requirements of IEC 61191-1, IEC 61191-2, IEC 61191-3 and IEC 61191-4.
This first edition partially cancels and replaces the IEC 61188-5 series of International Standards.
The significant technical changes with respect to the previous edition are listed in the Introduction and further detailed information and calculations can be found in Annex A.

Cartes imprimées et cartes imprimées équipées - Conception et utilisation - Partie 6-3: Conception de la zone de report - Description de la zone de report pour les composants à trous traversants (THT)

L’IEC 61188-6-2:2024 spécifie les exigences relatives aux pastilles et à la zone de report des cartes imprimées pour le montage par brasage des composants à pattes, basées sur les exigences relatives aux joints de brasure de l’IEC 61191-1 et de l’IEC 61191-3.
La présente partie de l’IEC 61188 spécifie les exigences relatives aux surfaces de brasage sur les cartes imprimées. Sont incluses les pastilles et la zone de report des composants montés en surface ainsi que les configurations de trous brasables pour les composants montés à trous traversants. Ces exigences reposent sur les exigences relatives aux joints de brasure des IEC 61191-1, IEC 61191-2, IEC 61191-3 et IEC 61191-4.
Cette première édition annule partiellement et remplace la série de Normes internationales IEC 61188-5.
Les principales modifications techniques par rapport à l’édition précédente sont énumérées dans l’Introduction et des informations détaillées et des calculs complémentaires sont fournis à l’Annexe A.

General Information

• Status: Published
• Publication Date: 08-Dec-2024
• ICS: 31.180 - Printed circuits and boards
• ICS: 31.190 - Electronic component assemblies
• Technical Committee: TC 91 - Electronics assembly technology
• Drafting Committee: WG 12 - TC 91/WG 12
• Current Stage: PPUB - Publication issued
• Start Date: 03-Jan-2025
• Completion Date: 09-Dec-2024

Relations

• Replaces: IEC 61188-5-5:2007 - Printed boards and printed board assemblies - Design and use - Part 5-5: Attachment (land/joint) considerations - Components with gull-wing leads on four sides
• Effective Date: 05-Sep-2023
• Replaces: IEC 61188-5-2:2003 - Printed boards and printed board assemblies - Design and use - Part 5-2: Attachment (land/joint) considerations - Discrete components
• Effective Date: 05-Sep-2023
• Replaces: IEC 61188-5-8:2007 - Printed board and printed board assemblies - Design and use - Part 5-8: Attachment (land/joint) considerations - Area array components (BGA, FBGA, CGA, LGA)
• Effective Date: 05-Sep-2023
• Replaces: IEC 61188-5-3:2007 - Printed boards and printed board assemblies - Design and use - Part 5-3: Attachment (land/joint) considerations - Components with gull-wing leads on two sides
• Effective Date: 05-Sep-2023
• Replaces: IEC 61188-5-4:2007 - Printed boards and printed board assemblies - Design and use - Part 5-4: Attachment (land/joint) considerations - Components with J leads on two sides
• Effective Date: 05-Sep-2023
• Replaces: IEC 61188-5-6:2003 - Printed boards and printed board assemblies - Design and use - Part 5-6: Attachment (land/joint) considerations - Chip carriers with J-leads on four sides
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 61188-6-3 ®
Edition 1.0 2024-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Circuit boards and circuit board assemblies – Design and use –
Part 6-3: Land pattern design – Description of land pattern for through hole
components (THT)
Cartes imprimées et cartes imprimées équipées – Conception et utilisation –
Partie 6-3: Conception de la zone de report – Description de la zone de report
pour les composants à trous traversants (THT)
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IEC 61188-6-3 ®
Edition 1.0 2024-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Circuit boards and circuit board assemblies – Design and use –

Part 6-3: Land pattern design – Description of land pattern for through hole

components (THT)
Cartes imprimées et cartes imprimées équipées – Conception et utilisation –

Partie 6-3: Conception de la zone de report – Description de la zone de report

pour les composants à trous traversants (THT)

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.180, 31.190 ISBN 978-2-8327-0069-3

– 2 – IEC 61188-6-3:2024 © IEC 2024
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 8
4 Description of a through hole component . 9
4.1 Component body . 9
4.2 Component leads . 9
5 Padstack . 10
5.1 Description . 10
5.2 Pad types . 10
5.2.1 General . 10
5.2.2 General . 10
5.2.3 Solder mask pads . 10
5.2.4 Outer layer pads . 11
5.2.5 Thermal pads . 11
5.2.6 Anti-pads . 11
5.3 Pad shapes . 11
5.4 Holes – Considerations for plated-through hole dimensioning . 11
5.5 Annular ring . 12
6 Requirements on lands for solder joints . 12
6.1 General . 12
6.2 Land/Pad dimensioning for leaded terminals . 14
6.3 Land shape for typical terminal shapes . 14
Annex A (informative) Determination, assessment and calculation of land pattern . 15
A.1 Consideration of creating holes . 15
A.1.1 General . 15
A.1.2 Punched . 15
A.1.3 Drilled . 16
A.1.4 Milled . 16
A.1.5 Laser drilled. 16
A.1.6 preformed / printed . 17
A.2 Determination of THT component assembly . 17
A.2.1 General . 17
A.2.2 Manual assembly . 17
A.2.3 Automated assembly . 18
A.2.4 Press fit component assembly . 18
A.3 Determination of the soldering process . 18
A.3.1 General . 18
A.3.2 Manual soldering . 18
A.3.3 Reflow soldering . 18
A.3.4 Wave soldering . 18
A.3.5 Other soldering processes . 18
A.4 Process flow to determine THT land pattern values . 19
A.4.1 Purpose . 19
A.4.2 Hole creation process . 20

A.4.3 Drill tolerance . 21
A.4.4 Solder gap . 21
A.4.5 Copper foil . 23
A.4.6 Layer positioning . 23
A.4.7 Circuit board stack-up . 24
A.4.8 Land size (pad-size) . 24
A.4.9 Examples to be enclosed . 25
Bibliography . 31

Figure 1 – Leaded component . 9
Figure 2 – Round lead . 9
Figure 3 – Square lead . 9
Figure 4 – Rectangle lead . 9
Figure 5 – Padstack . 10
Figure 6 – Terminal diameter, annular ring . 13
Figure 7 – Basic design flow diagram for land pattern for THT . 14
Figure A.1 – Circuit board manufacturing and assembly . 15
Figure A.2 – Figure oblong pin . 16
Figure A.3 – Protrusion of component terminal . 17
Figure A.4 – Process flow of determining a land pattern . 19
Figure A.5 – Proportional annular ring of a TH Terminal . 20
Figure A.6 – Determination of gap ratio proportional to substrate thickness . 22
Figure A.7 – Overview on the options of THT-calculation . 25

Table 1 – Layer function and pad types.
...