IEC 61189-2-808:2024

Test methods for electrical materials, printed board and other interconnection structures and assemblies - Part 2-808: Thermal resistance of an assembly by thermal transient method

IEC 61189-2-808:2024 describes the thermal transient method to characterize the thermal resistance of an assembly consisting of a heat source (e.g. power device), an attachment material (e.g. solder) and a dielectric layer with electrode. This method is suitable to determine the thermal resistance of materials and assembly methods as well as to optimize the thermal flux to a heat sink.
NOTE: This method is not intended to measure and specify the value of the thermal resistance of a dielectric material. For that purpose, other standards exist. Examples are given in Annex A.

Méthodes d'essai pour les matériaux électriques, les cartes imprimées et autres structures et assemblages d'interconnexion - Partie 2-808 : Résistance thermique d'un assemblage par la méthode du transitoire thermique

L’IEC 61189-2-808:2024 décrit la méthode du transitoire thermique pour caractériser la résistance thermique d'un assemblage constitué d'une source de chaleur (par exemple, un dispositif de puissance), d'un matériau de fixation (par exemple, une brasure) et d'une couche diélectrique avec électrode. Cette méthode permet de déterminer la résistance thermique des matériaux et des méthodes d'assemblage ainsi que d'optimiser le flux thermique vers un dissipateur thermique.
NOTE: Cette méthode n’est toutefois pas destinée à mesurer et à spécifier la valeur de la résistance thermique d'un matériau diélectrique. Il existe d’autres normes à cet effet. Des exemples sont donnés à l'Annexe A.

General Information

• Status: Published
• Publication Date: 24-Apr-2024
• ICS: 31.180 - Printed circuits and boards
• Technical Committee: TC 91 - Electronics assembly technology
• Drafting Committee: WG 10 - TC 91/WG 10
• Current Stage: PPUB - Publication issued
• Start Date: 17-May-2024
• Completion Date: 25-Apr-2024

Standards Content (Sample)

IEC 61189-2-808 ®
Edition 1.0 2024-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Test methods for electrical materials, printed board and other interconnection
structures and assemblies –
Part 2-808: Thermal resistance of an assembly by thermal transient method

Méthodes d'essai pour les matériaux électriques, les cartes imprimées et autres
structures et assemblages d'interconnexion –
Partie 2-808 : Résistance thermique d'un assemblage par la méthode du
transitoire thermique
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IEC 61189-2-808 ®
Edition 1.0 2024-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Test methods for electrical materials, printed board and other interconnection

structures and assemblies –
Part 2-808: Thermal resistance of an assembly by thermal transient method

Méthodes d'essai pour les matériaux électriques, les cartes imprimées et autres

structures et assemblages d'interconnexion –

Partie 2-808 : Résistance thermique d'un assemblage par la méthode du

transitoire thermique
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.180  ISBN 978-2-8322-8804-7

– 2 – IEC 61189-2-808:2024 © IEC 2024
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Objective . 5
5 Test specimen . 6
6 Test equipment and procedures . 7
6.1 Test method and recommended test parameters . 7
6.2 Test equipment . 7
6.3 Test procedure . 8
7 Test result . 8
8 Report . 9
Annex A (informative) Additional test methods for thermal resistance . 11
Annex B (informative) Thermal resistance of die attach materials . 13
B.1 Test specimen . 13
B.2 Die attach materials . 13
B.3 Test result. 14
Annex C (informative) Uncertainty and repeatability for thermal resistance test . 16
C.1 Test specimen . 16
C.2 Test result. 16
Annex D (informative) Thermostat equipment . 18
Bibliography . 20

Figure 1 – Structure of an assembly . 6
Figure 2 – The fabricated test sample . 6
Figure 3 – Test structure for measuring thermal resistance . 8
Figure 4 – Test result for thermal resistance of an assembly . 9
Figure B.1 –Structure of test sample using die attach material . 13
Figure B.2 –The fabricated test sample using die attach material . 13
Figure B.3 – Test graph for die attach materials . 15
Figure C.1 – Test structure for measuring thermal resistance . 16
Figure C.2 – Test result for thermal resistance of assembly . 16
Figure D.1 – Connection of the thermostat unit to the T3Ster® main system unit . 18
Figure D.2 –Calibration diagram recorded by the T3Ster® thermostat . 19

Table 1 – Test result for thermal resistance of an assembly . 9
Table A.1 – ASTM C1113 . 11
Table A.2 – ASTM E1461 . 11
Table A.3 – ASTM D5470 . 12
Table B.1 – Properties for die attach materials . 14
Table B.2 – Test result for die attach materials . 15
Table C.1 – Test result for thermal resistance of assembly . 17

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
TEST METHODS FOR ELECTRICAL MATERIALS, PRINTED BOARD AND
OTHER INTERCONNECTION STRUCTURES AND ASSEMBLIES –

Part 2-808: Thermal resistance of an assembly
by thermal transient method
FOREWORD
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