A switch electrically connected to a first terminal and a second terminal. A first comparator detects a load open state where the switch is off and a load is not connected to the second terminal. Upon detecting, a clamp circuit clamps the voltage of the second terminal to a clamp voltage higher than a first reference voltage and lower than an input voltage. A second comparator detects an output-to-supply short circuit state where the switch is off and the second terminal is connected to the power supply. A capacitor with one terminal connected to the second terminal and another terminal connected to a third terminal. A bootstrap circuit supplies a charge current to the third terminal at a constant voltage. A clamp voltage rise prevention circuit prevents the clamp voltage of the clamp circuit from rising, when the first comparator detects the load open state.