A high frequency isolated resonant gate driver for SiC power MOSFET with asymmetrical ON/OFF voltage

The resonant gate driver is the most efficient method to reduce the gate drive loss. However, the conventional resonant gate driver cannot be implemented for SiC power MOSFET because of the asymmetrical breakdown voltage of the gate-source. To improve both the efficiency and the reliability of the power converter, a resonant gate driver with a level shift circuit to achieve adjustable asymmetrical on/off voltage for SiC power MOSFET is proposed in this paper. The operating principle of the level shift circuit and the transition of the power MOSFET are described. A prototype is built to verify the effectiveness of the proposed gate driver. Test result shows that the proposed gate drive circuit achieves +13V/-4V gate-source voltages. Besides, the gate drive loss is reduced for over 50% compared to conventional voltage source driver.