An Ultrafast Desaturation-Based Protection Circuit for GaN HEMTs

Gallium nitride high electron mobility transistors (GaN HEMTs) have an advantage in high switching speed and high frequency applications. However, the protection circuit for GaN HEMTs requires a fast response time due to the low robustness of short-circuit condition of GaN HEMTs. In addition, the high switching speed of GaN HEMTs generates severe noise, which causes a false-triggering for the protection circuit. This article is focused on analyzing the effect of switching noise on the protection circuit and proposes the protection circuit for GaN HEMTs with fast response speed and strong noise immunity. The protection circuit has been verified by SPICE simulation. The simulation results show that the protection delay of protection circuit is within 101 ns with strong noise immunity at normal operation.