Rohm Co., Ltd.

Takashi Sawada

Hirotaka Otake

Masao Saito

Tatsuya Yanagi

Seiya Kitagawa

A gate drive circuit has a capacitor and a gate drive voltage source connected in series with a gate terminal of a voltage-driven switching device. The gate drive source voltage feeds, as a gate drive voltage, a voltage higher than the sum of the voltage applied to a gate-source parasitic capacitance of the switching device when the switching device is in a steady ON state and the voltage applied to, of any circuit component interposed between the gate drive voltage source and the gate terminal of the switching device, a circuit component other than the capacitor (such as an upper transistor forming the output stage of the driver). No other circuit component (such as a resistor connected in parallel with the capacitor) is essential but the capacitor as the sole circuit component to be directly connected to the gate terminal of the switching device.

Gate drive circuit

A power module () includes a first high-side main-circuit MOSFET () and a second low-side main-circuit MOSFET () connected in series thereto. The series circuit of the MOSFETs () is connected in parallel to a power source (). A first short-circuit MOSFET () is connected between the gate and the source of the first main-circuit MOSFET (). A second short-circuit MOSFET () is connected between the gate and the source of the second main-circuit MOSFET ().

Growing community of inventors

Kyoto, Japan

Takashi Sawada