An analysis of false turn-on mechanism on high-frequency power devices

In high efficiency and high temperature industrial applications, wide bandgap semiconductor devices, such as: Gallium Nitride (GaN) and Silicon Carbide (SiC), are getting great attention due to their outstanding performance. However, a false turn-on phenomenon can be produced by the switching noise because wide bandgap devices have low threshold voltage. Consequently, the efficiency of a switched-mode power supply using these devices can be decreased. This paper analyzes the gate noise performance using experimental tests and circuit simulations focusing on the parasitic parameters of the power devices. Additionally, this analysis was conducted on the base of the theoretical calculation using an equivalent circuit modeling. As a result, it was obtained that Si MOSFETs and GaN HEMT have different false turn-on mechanism.