A semiconductor circuit includes an operational amplifier, a voltage drop circuit, and a switch. The operational amplifier has an output terminal connected to an active element that produces a load drive current. A reference voltage is input to the non-inverting input of the operational amplifier. The voltage drop circuit drops a voltage outputted from the operational amplifier. The switch applies a voltage corresponding to a predetermined current flowing when the active element is on to the inverting input of the operational amplifier in a first interval in which the active element is on in response to a predetermined voltage from the operational amplifier. The switch allows the voltage dropped by the voltage drop circuit to be input to the inverting input in a second interval in which the active element is off, thereby shortening a time period until the load drive current starts to flow.