Patent ID: 9048829
Filing Date: 2015-06-02
Classification: H03K

Abstract:
1. A power semiconductor device driving circuit comprising: a power semiconductor device formed of a semiconductor switching device, which controls a current supplied to a first terminal and a second terminal based on a gate voltage applied to a gate terminal, the first terminal and the second terminal being a high-side terminal and a low-side terminal; a gate driving circuit for controlling the gate voltage applied to the gate terminal of the power semiconductor device; a discharge terminal provided at a position separated from the first terminal by a predetermined distance and electrically insulated from the first terminal to cause a discharge between the first terminal and the discharge terminal when the voltage at the first terminal rises by generation of a surge and reaches a dielectric breakdown voltage; an auxiliary power source for supplying an auxiliary power voltage close to the threshold voltage of the power semiconductor device but smaller than a voltage required to fully turn on the power device, wherein the auxiliary power source is powered separately from the surge in providing the auxiliary power voltage; and a gate charge circuit, which turns on the power semiconductor device by charging a gate terminal of the power semiconductor device based on the discharge between the first terminal and the discharge terminal and lowers the voltage of the first terminal by a current flowing between the first terminal and the second terminal, wherein the discharge terminal includes a gate control terminal provided in the gate driving circuit; and the gate charging circuit includes a voltage holding circuit, which is provided in the gate driving circuit and turns on the power semiconductor device by holding the gate terminal in a state that the auxiliary power source is coupled to the gate terminal to couple the auxiliary power voltage to the gate terminal for a predetermined period when the surge voltage is applied to the gate control terminal.