Active Gate Driver and Management of the Current Switching Speed in GaN Transistors During Tum-On

Abstract

This paper describes the principle of an active gate driver to control the high current switching speed generated during the tum-on of GaN HEMT transistors. The proposed circuit requires a common-mode parasitic inductance of 1 nH to provide the necessary image of the current slope. The proposed scheme is comparable to a variation of gate resistance of one decade without the inconvenience of the gate resistance. The approach is first validated by circuit simulation then experimentally. The advantages of such an approach are then demonstrated thanks to the comparison with a conventional passive control method.