A Gate Driver for Fast Switching and EMI Suppression of Cascode GaN-Based Converter

Due to the complex structure and unique characteristics of cascode GaN devices, the traditional gate driver cannot satisfy or take the full advantage of the cascode GaN. This paper presents a SPICE modeling method that takes into account circuit layout and device parasitic to analyze switching behavior under the gate driving parameters, then a gate driver(GD) is proposed, which consisting of separated turn on and turn off path by different flying capacitors and gate resistors to control gate loop impedances at different transient stage. Compare with the traditional gate driver, the proposed GD can accelerate the switching speed and suppress the overshoot, oscillation and electromagnetic interference (EMI) produced by high di/dt and dv/dt while reduce the power loss. The experiment validated the effectiveness of proposed GD.