Hitachi, Ltd.

Hitachi Ulsi Engineering Corp.

Ken Uchid

Isao Yoshida

Masayoshi Kobayashi

Kozo Sakamoto

Tetsuo Iijima

Shigeo Otaka

Hideki Tsunoda

Harutora Shono

An improvement in conditions that protective functions of an insulated gate semiconductor device with a protection circuit incorporated therein are performed, an improvement in the cutoff of heating, the prevention of malfunctions and an improvement in ease of usage can be achieved. The insulated gate semiconductor device of the present invention comprises a power insulated gate semiconductor element (M9), at least one MOSFET (M1 through M7) for a protection circuit, for controlling the power insulated gate semiconductor element, a constant-voltage circuit using forward voltages developed across diodes (D2a through D2f) for the constant-voltage circuit, and voltage restricting diodes (D1 and D0a through D0d) for controlling the upper limit of a power supply voltage of the constant-voltage circuit. Power to be supplied to the voltage restricting diodes is supplied from an external gate terminal of the power insulated gate semiconductor element. The present invention can bring about an advantageous effect that an improvement in reliability of the insulated gate semiconductor device and an improvement in the ease of use can be achieved.

Insulated gate semiconductor device and driving circuit device and

Growing community of inventors

Higashiyamato, Japan

Ken Uchid