DIN EN IEC 61189-2-808:2025-08

This part of IEC 61189 describes the thermal transient method to characterize the thermal resistance of an assembly consisting of a heat source (for example, power device), an attachment material (for example, 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. This document covers: X, Y, and Z. This document covers: - test specimens, - test equipment and procedures, - test results, - test reports, - additional methods for testing thermal resistance, - thermal resistance of chip-bonding materials, - uncertainty and repeatability in thermal resistance testing, and - thermostatic equipment. 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. Application of this document increases investment security for manufacturers and users, provides testing laboratories and manufacturers with defined specifications for testing, and enhances product compatibility between manufacturers.