IEC 62326-20:2016

Printed boards - Part 20: Printed circuit boards for high-brightness LEDs

IEC 62326-20:2016 specifies the properties of the printed circuit board (hereafter described as PCB) for high-brightness LEDs. Many aspects of the PCB for high-brightness LEDs are identical with those of ordinary PCBs, therefore, some aspects of this standard also describe general aspects. This edition includes the following significant technical changes with respect to the previous edition:
a) this edition focuses on the technical content of the printed circuit board for high-brightness LEDs;
b) the figures related to the printed circuit board for high-brightness LEDs have been refined.

Cartes imprimées - Partie 20: Cartes de circuits imprimés destinées aux LED à haute luminosité

L'IEC 62326-20:2016 spécifie les propriétés des cartes de circuits imprimés (ci après dénommées PCB, Printed Circuit Board) destinées aux LED à haute luminosité. Les PCB destinées aux LED à haute luminosité partagent avec les PCB ordinaires de nombreux aspects. Certains aspects d'ordre général sont donc décrits dans la présente norme. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
a) la présente édition se concentre sur le contenu technique des cartes de circuits imprimés destinées aux diodes électroluminescentes (LED) à haute luminosité;
b) les figures relatives aux cartes de circuits imprimés destinées aux LED à haute luminosité ont été affinées.

General Information

• Status: Published
• Publication Date: 02-Feb-2016
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 29.120.50 - Fuses and other overcurrent protection devices
• ICS: 29.240.10 - Substations. Surge arresters
• ICS: 31.180 - Printed circuits and boards
• Technical Committee: TC 91 - Electronics assembly technology
• Drafting Committee: WG 4 - TC 91/WG 4
• Current Stage: PPUB - Publication issued
• Start Date: 31-Jan-2016
• Completion Date: 03-Feb-2016

Relations

• Replaces: IEC PAS 62326-20:2011 - Printed boards - Part 20: Electronic circuit board for high-brightness LEDs
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 62326-20 ®
Edition 1.0 2016-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Printed boards –
Part 20: Printed circuit boards for high-brightness LEDs

Cartes imprimées –
Partie 20: Cartes de circuits imprimés destinées aux LED à haute luminosité

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IEC 62326-20 ®
Edition 1.0 2016-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Printed boards –
Part 20: Printed circuit boards for high-brightness LEDs

Cartes imprimées –
Partie 20: Cartes de circuits imprimés destinées aux LED à haute luminosité

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.180 ISBN 978-2-8322-3152-4

– 2 – IEC 62326-20:2016 © IEC 2016
CONTENTS
FOREWORD . 6
1 Scope . 8
2 Normative references. 8
3 Terms, definitions and abbreviations . 8
3.1 Terms and definitions . 8
3.2 Abbreviations . 8
4 Classification and class of the printed circuit board for high-brightness LEDs . 9
5 Design rules and allowance . 10
5.1 Panel and board sizes . 10
5.1.1 Board size . 10
5.1.2 Allowance of dimensions . 11
5.1.3 Perforation and slit . 11
5.1.4 V-cut . 12
5.2 Total board thickness . 13
5.3 Holes . 14
5.3.1 Insertion holes and vias . 14
5.3.2 Datum hole . 16
5.3.3 Assembly hole (a through-hole without wall plating) . 16
5.4 Conductor . 17
5.4.1 Width of conductor pattern and its allowance . 17
5.4.2 Distance between conductors and its allowance . 17
5.4.3 Thickness of the insulating layer . 18
5.5 Printed contact . 18
5.5.1 Allowance of the distance between the centers of two adjacent printed
contacts . 18
5.5.2 Allowance of the terminal width of printed contacts . 19
5.5.3 Shift of the center of printed contacts on front and back sides of a board . 19
5.6 Land pattern . 20
5.6.1 Allowance of the distance between the centers of two lands . 20
5.6.2 Allowance of the width of a land . 20
5.6.3 Land diameter and its allowance for BGA/CSP . 21
5.7 Fiducial mark and mark for component positioning . 22
5.7.1 Typical form and size of the fiducial mark . 22
5.7.2 Dimensional allowance of fiducial mark and component positioning mark . 23
5.7.3 Position allowance of the component positioning mark . 23
5.8 Interlayer connection – Copper plating . 23
6 Quality . 24
6.1 Gap between conductor and the wall of a component insertion hole or a via . 24
6.2 Positional deviation between conductor layers of a multilayer board . 24
6.3 Minimum land width . 24
6.4 Surface treatment . 25
6.4.1 Gold plating for printed contact . 25
6.4.2 Other surface treatment . 26
6.5 Defects of solder resist . 26
6.6 Symbol mark . 28
6.6.1 General . 28

6.6.2 Conductor surface . 28
6.6.3 Between conductors . 28
6.6.4 Defects within insulating layers . 29
6.6.5 Routing and drilling . 30
6.6.6 Conductor pattern . 30
6.7 Land . 30
6.8 Land of a land pattern . 31
6.9 Defects in a land for BGA/CSP mounting . 32
6.10 Printed contact . 32
7 Performance and test methods . 34
7.1 Resistance of conductors . 34
7.2 Current proof of conductor and plated through hole . 35
7.3 Observation of component mountings and vias . 36
7.3.1 Observation with standard conditions . 36
7.3.2 Observation after thermal shock test . 38
8 Marking, packaging and storage . 39
8.1 Marking on a product . 39
8.2 Marking on the package . 39
8.3 Packaging and storage . 40
8.3.1 Packaging . 40
8.3.2 Storage . 40
Annex A (informative) Classification and class of the PCB for high-brightness LEDs . 41
Bibliography . 46

Figure 1 – Example of a classification and its application . 10
Figure 2 – Board arrangement in a panel .
...