Patent ID: 7750437

Claim:
A semiconductor device, comprising: a rectifier circuit and an integrated circuit which are formed from a semiconductor substrate of a first conduction type and are provided on a top surface of the semiconductor substrate; a first well region of a second conduction type, formed within the semiconductor substrate of the first conduction type; a second well region of the first conduction type, formed within the first well region; and, a diode region of the second conduction type, formed within the second well region, which together with the second well region forms a diode, wherein the rectifier circuit comprises a plurality of the diodes; an input power supply terminal which changes between positive potential and negative potential is connected to the second well region and first well region of a first diode and to the diode region of a second diode and is provided on the top surface of the semiconductor substrate; and, a current supply terminal is provided on the top surface of the semiconductor substrate, connected to the semiconductor substrate and connected to a prescribed power supply, and which supplies current to a PN junction between the first well region and the semiconductor substrate when the potential of the input power supply terminal is negative.