Analytical modeling of SiC MOSFET during switching transient

Abstract

Silicon carbide (SiC) MOSFET has become a nice alternative to silicon (Si) IGBT and MOSFET. However, more serious electromagnetic interference (EMI) issues are brought by fast switching characteristics of SiC MOSFET as well. In order to understand the principle of these EMI issues, an analytical model is proposed in this paper. With the full consideration of parasitic inductances and non-linearities of the junction capacitances, the model is proposed to describe the switching transient of SiC MOSFET. Meanwhile, a novel linear function is used to represent the relationship between the channel current and the gate-source voltage of SiC MOSFET, and the model can depict the switching transient in wide-range load current. Finally, the effectiveness of the analytical model is verified by comparison between model-calculated and LTspice-simulated results.