Protection circuit

A protection circuit (1) includes a power supply terminal (VDD), a ground terminal (GND), a control unit (11) connected to the power supply terminal (VDD) and the ground terminal (GND), and a supply unit (12) connected to the power supply terminal (VDD) and the ground terminal (GND), for preventing application of voltage in a reverse direction to a circuit unit (C) having a predetermined function. In this case, the control unit (11) generates a control potential which controls the control unit (11) and the supply unit (12) in accordance with a potential supplied from the power supply terminal (VDD) and a potential supplied from the ground terminal (GND). The supply unit (12) is configured to be capable of supplying current to a circuit unit (C) connected to a subsequent stage on the basis of a potential supplied from the power supply terminal (VDD), a potential supplied from the ground terminal (GND), and the control potential generated by the control unit (11).