A semiconductor device comprising: a drive transistor, being an N-channel MOS transistor, configured to control supply of a current flowing through a path between a voltage supplying terminal supplied with a battery voltage (Vbat) and an external output terminal coupled to a load; a current detector unit that includes: a sense transistor, being an N-channel MOS transistor, through which a current proportional to the current flowing through the drive transistor flows, a drain of the sense transistor being coupled to the voltage supplying terminal, a gate of the sense transistor being connected to a gate of the drive transistor; and a current monitor that is coupled to a source of the drive transistor and monitors the current flowing through the sense transistor, a controller unit to generate a pulse signal corresponding to a value of the current detected by the current detector unit, the pulse signal being configured to control the biasing supplied to the gate of the drive transistor; a voltage monitor to monitor a voltage of the external output terminal; and a pre-driver that includes: a first switching unit configured to receive the pulse signal, and control charge and discharge to the gate of the drive transistor based on the pulse signal; and a second switching unit configured to receive the pulse signal, and control charge and discharge to the gate of the drive transistor based on the pulse signal in cooperation with the first switching unit, wherein the pre-driver performs charge and discharge to the gate of the drive transistor at a first charge and discharge speed by switching on the first switching unit and switching off the second switching unit based on the pulse signal and a monitored result of the voltage monitor indicating that the voltage of the external output terminal has not reached a prescribed voltage, and wherein the pre-driver performs charge and discharge to the gate of the drive transistor at a second charge and discharge speed faster than the first charge and discharge speed by switching on the first switching unit and switching on the second switching unit based on the pulse signal and a monitored result of the voltage monitor indicating that the voltage of the external output terminal has reached the prescribed voltage. a drive transistor, being an N-channel MOS transistor, configured to control supply of a current flowing through a path between a voltage supplying terminal supplied with a battery voltage (Vbat) and an external output terminal coupled to a load; a current detector unit that includes: a sense transistor, being an N-channel MOS transistor, through which a current proportional to the current flowing through the drive transistor flows, a drain of the sense transistor being coupled to the voltage supplying terminal, a gate of the sense transistor being connected to a gate of the drive transistor; and a current monitor that is coupled to a source of the drive transistor and monitors the current flowing through the sense transistor, a sense transistor, being an N-channel MOS transistor, through which a current proportional to the current flowing through the drive transistor flows, a drain of the sense transistor being coupled to the voltage supplying terminal, a gate of the sense transistor being connected to a gate of the drive transistor; and a current monitor that is coupled to a source of the drive transistor and monitors the current flowing through the sense transistor, a controller unit to generate a pulse signal corresponding to a value of the current detected by the current detector unit, the pulse signal being configured to control the biasing supplied to the gate of the drive transistor; a voltage monitor to monitor a voltage of the external output terminal; and a pre-driver that includes: a first switching unit configured to receive the pulse signal, and control charge and discharge to the gate of the drive transistor based on the pulse signal; and a second switching unit configured to receive the pulse signal, and control charge and discharge to the gate of the drive transistor based on the pulse signal in cooperation with the first switching unit, a first switching unit configured to receive the pulse signal, and control charge and discharge to the gate of the drive transistor based on the pulse signal; and a second switching unit configured to receive the pulse signal, and control charge and discharge to the gate of the drive transistor based on the pulse signal in cooperation with the first switching unit, wherein the pre-driver performs charge and discharge to the gate of the drive transistor at a first charge and discharge speed by switching on the first switching unit and switching off the second switching unit based on the pulse signal and a monitored result of the voltage monitor indicating that the voltage of the external output terminal has not reached a prescribed voltage, and wherein the pre-driver performs charge and discharge to the gate of the drive transistor at a second charge and discharge speed faster than the first charge and discharge speed by switching on the first switching unit and switching on the second switching unit based on the pulse signal and a monitored result of the voltage monitor indicating that the voltage of the external output terminal has reached the prescribed voltage.