Effect of Parameters Variability on the Performance of SiC MOSFET Modules

This paper introduces a statistical analysis of the impact of devices parameters dispersion on the performances of parallel connected SiC MOSFETs. To this purpose, the statistical fluctuations of threshold voltage and current factor are evaluated on a set of 20 MOSFETs. In order to assess the effects of parameters spread in a real operating condition, the electrothermal simulation of a 200kHz synchronous buck converter is performed. Subsequently, an investigation of the switching energy unbalance, as a function of parameters distribution tolerances, is achieved through several sets of Monte Carlo electrothermal simulations. The results aim at aiding both the design of multi-chip configurations and the selection of appropriate fabrication process rejection boundaries.