Semiconductor device and system

A semiconductor device includes an inductor selectively connected to a power supply voltage and configured to store and release energy; a first transistor connected between the power supply voltage and the inductor and configured to provide the power supply voltage to the inductor; a second transistor connected to the first transistor in series, connected between the inductor and a ground voltage, and configured to provide the ground voltage to the inductor; a modulator configured to provide a modulation signal to a control circuit configured to control the first and second transistors by performing pulse width modulation (PWM); a current sensor configured to sense an amount of current passing through the first transistor and generate a first output signal based on the sensed amount of current; and a first overcurrent protection output generator configured to generate a second output signal based on the first output signal and a first reference signal.