Patent ID: 7768759

Claim:
A control circuit of a semiconductor device having an over-heat protecting function, comprising: a semiconductor element which supplies an electric power from a power source to a load; an over-heat protecting unit for protecting an over-heat inside the semiconductor device, the over-heat protecting unit having: a temperature detecting section which detects a rise in temperature of the semiconductor device; a latch section which holds a detected output of the temperature detecting section; and a gate interrupting section which interrupts an input to a gate of the semiconductor element in accordance with the output of the latch section; a control unit which supplies a PWM signal for turning on/off the semiconductor element; a driving electric power supply unit which supplies a driving electric power for driving the over-heat protecting unit; and a timer unit which allows the driving electric power supply unit to supply the driving electric power for a predetermined period when the gate interrupting section interrupts the input to the gate of the semiconductor element and the control unit stops to supply the PWM signal to the semiconductor element.