Comparison of Gate-drive Switching Control for GaN HEMT Power Devices

GaN HEMT switching devices are typically controlled with a simple resistive voltage-source gate-drive circuit, which has limitations for dV/dt and di/dt controllability. This paper explores two additional methods of gate control: An open-loop current-drive; and closed-loop gate control, using a combination of current-drive, voltage measurement, and feedback control loop. A reduced-order modelling technique is applied. The authors present simulation results for each of these gate-drive methods, along with experimental test results to verify accuracy and achievable performance.