Research on precise test method for switching performance of high speed SiC MOSFET

In order to precisely test the switching performance of high speed SiC MOSFET, this paper researches the test method. The simulation switching waveforms considering the parasitic inductors are compared to the switching waveforms without considering the parasitic inductors in this paper. The distinctions of comparative results are obvious and prove the effects of parasitic inductors on switching performance should not be neglected. Concerning the passive voltage, the bandwidth and the parasitic inductor in the grounding lead can affect the tested results. This paper compares the switching waveforms tested by three passive voltage probes, the bandwidth of which are 150MHz, 300MHz and 500MHz, respectively. This paper compares the switching waveforms tested by the BNC adapter, the grounding spring and the grounding lead. When testing the switching current, the coaxial shunt, the sample resistor, the split core current probe or the current transformer can be employed. This paper compares the switching waveforms tested by four kinds of current test equipment. In addition, test points are also important for testing the switching performance of high speed SiC MOSFET precisely, and this paper compares the switching waveforms at different test points.