Low Inductive Characterization of Fast-Switching SiC MOSFETs and Active Gate Driver Units

Abstract

Accurate switching device characterization is necessary for effectively utilizing the technological advantages of Silicon Carbide (SiC) Power Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) over their Silicon (Si) Insulated-Gate Bipolar Transistor (IGBT) counterparts. With switching times of few nanoseconds, the unprecedented switching speed of SiC semiconductor devices challenges today's converter and characterization setup designs in regard to parasitic layout inductances for optimal conversion and reliable characterization data. Furthermore, active gate driving is a key to unlock the potential of SiC MOSFETs, but requires performance assessment prior to integration. This article presents a low-inductive test platform for flexible and high-accuracy characterization of fast-switching SiC MOSFETs and active gate drivers evaluation. The test circuit delivers high quality characterization data that is comparable with a commercial dynamic power device characterizer. In addition to the conventional hard-switching double-pulse tests with a two-level voltage source gate driver, the test circuit offers soft-switching and gate driver evaluation capability in addition. This test platform is a valuable tool for obtaining reliable characterization data to develop more accurate SiC MOSFET simulation models, and evaluate the combination of gate driver and MOSFET prior to the prototyping phase of a converter.