Patent ID: 8044639

Claim:
A selector circuit including: a first input terminal via which a first input voltage is input from an external source; a second input terminal via which a second input voltage is input from another external source; an output terminal which outputs one of the first input voltage or the second input voltage; a first MOSFET (Metal Oxide Semiconductor Field Effect Transistor) and a second MOSFET, which are provided in series between the first input terminal and the output terminal; a third MOSFET and a fourth MOSFET, which are provided in series between the second input terminal and the output terminal; and a control unit which controls the ON/OFF operations of the first MOSFET and second MOSFET pair and the third MOSFET and fourth MOSFET pair, wherein a connection of a back gate of the first MOSFET and a connection of a back gate of the second MOSFET are formed such that at least one body diode of the first MOSFET and at least one body diode of the second MOSFT are arranged in opposing directions, wherein a connection of a back gate of the third MOSFET and a connection of a back gate of the fourth MOSFET are formed such that at least one body diode of the third MOSFET and at least one body diode of the fourth MOSFET are arranged in opposing directions; and wherein the control unit comprises: a first charge pump circuit configured such that, when an instruction is given to switch the first and second MOSFETs to the ON state, the first charge pump circuit steps up the first input voltages and outputs the first input voltage thus stepped up to the gates of the first and second MOSFETs; and a second charge pump circuit configured such that, when an instruction is given to switch the third and fourth MOSFETs to the ON state, the second charge pump circuit steps up the second input voltage, and outputs the second input voltage thus stepped up to the gates of the third and fourth MOSFETs.