A Multilevel Gate Driver Operating with a Single Voltage Supply and Simple Control Signals for Monolithic Integration of Power GaN HEMT

This paper presents a monolithic Gallium Nitride Integrated Circuit (GaN IC) which integrates a multilevel gate driver and a power Gallium Nitride High Electron Mobility Transistor (GaN HEMT). The multilevel gate driver is effective to prevent false turn-on and reduce reverse conduction loss in the half bridge converter with simple control signals. It can apply negative voltage without any additional voltage supply by using a capacitor. In order to improve performance of power converters, we monolithically integrated the multilevel gate driver and a power HEMT. To further improve efficiency, we also fabricated another type of a GaN IC which integrates two power HEMTs for half-bridge configuration and the multilevel gate driver with an MIM capacitor. The GaN ICs were fabricated using a GaN-on-SOI process. We evaluated the proposed GaN ICs implemented in a synchronous rectifier (SR) buck converter. Measurement results show that the proposed GaN ICs successfully operated. The GaN IC with half-bridge configuration and MIM capacitor achieves higher efficiency and smaller voltage spike than the GaN IC without them.