Design of a 5MHz Half-bridge Gate Driver for GaN HEMTs with Adaptive Output Current

抄録

In this paper, a half-bridge gate driver with adaptive output current for GaN HEMTs is introduced. The output drive current of the driver is adapted to the load of GaN HEMTs, by adjusting the W/L size of drive transistors. The rise time of driver is achieved to be basically constant by the adaptive output current adjustment for different load, so noise can be effectively immunized and working efficiency is improved. Based on the proposed adaptive output current drive circuit, a half-bridge gate driver is designed and implemented in the 180nm BCD process. Tested results show the driver has a constant rise time of about 5ns under 5MHz with C_L of 0.5nF, 2.0nF, and 3.5nF respectively.