All-GaN Two-stage Turn-off Circuits for Over-current Protection in GaN Monolithic Power ICs

In this paper, the circuit design of the all-GaN Two-stage Turn-off Over-Current Protection circuit (TT-OCP) is proposed. The TT-OCP can realize the over-current protection of GaN power HEMTs through a two-stage turn-off method combining the adjustable gate-clamping and adjustable hard turn-off, which can realize the suppression of drain overshoot voltage caused by fast turn-off of GaN power HEMT in over-current condition. Compared with the conventional over-current protection integrated circuit, the simulation results of the proposed TT-OCP show that the overshoot voltage is suppressed by 34.9% under the same conditions.