Patent ID: 8362812

Claim:
A switching gate driver of an insulated gate bipolar transistor) (IGBT) device, the switching gate driver comprising: a resistor unit configured to control a gate current of the IGBT device, the resistor unit comprising a fixed-resistor unit and a variable resistor unit connected in parallel with the fixed-resistor unit, the variable resistor unit comprising a plurality of switches and resistors connected in serial with the plurality of switches; and a voltage reader configured to control the variable resistor unit according to a collector-emitter voltage of the IGBT device, wherein the voltage reader turns the plurality of switches on when the collector-emitter voltage goes less than a first reference voltage at a turn-on operation of the IGBT device, and the voltage reader turns the plurality of switches off when the collector-emitter voltage goes greater than a second reference voltage at a turn-off operation of the IGBT device.