IEC 61189-2-808:2024

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
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