Design and Optimization of the Driver Circuit for Non-Insulating Gate GaN-Transistors Enabling Fast Switching and High-Frequency Operation

Abstract:
This work clarifies the special characteristics of GaN transistors with non-insulating gate and challenges to drive them. Different existing driver circuits are compared, and the issues occurring in high -frequency or a large duty cycle operations are illustrated. An improved driver circuit with an active discharge path is proposed and verified experimentally. The proposed driver circuit adds only one auxiliary circuit component without the need for additional control circuitry. This circuit can drive non-insulating gate type GaN transistors in the MHz range, allowing fast switching in a wide duty cycle range and ensuring a fixed turn-off voltage which improves reliability.