Development of High-speed Current Switch Box for Transient Thermal Characterization of SiC Power Modules

The static test method utilizes the temperature dependency of I-V characteristics on power devices to characterize the transient thermal resistance of power module packages. SiC power devices, which have high thermal conductivity, require a high-speed cut-off of a large heating current within 50 microseconds to characterize the bare die itself. However, the switching surge voltage continues over several tens of microseconds when the large heating current shunts off. This paper develops a current switch box in a developing transient thermal characterization system for SiC power devices, and its performance is experimentally evaluated. The transient thermal characteristics of SiC power modules are also performed with the developed measurement system.