Patent ID: 7705485

Claim:
A power source which includes a first power source unit that applies a first operating voltage to a control unit and a second power source unit that applies a second operating voltage to a unit to be controlled by the control unit, comprising: a first electric power supplying unit that supplies electric power to the first power source unit; and a second electric power supplying unit that supplies the electric power to the second power source unit; wherein the first electric power supplying unit includes a parallel circuit composed of a main power switch and a first switching unit capable of being electrically controlled, the electric power is supplied to the first power source unit by turning on the main power switch, and the first switching unit is turned on by a voltage output from the second power source unit; and the second electric power supplying unit includes a series circuit composed of the main power switch and a second switching unit capable of being electrically controlled, and the electric power is supplied to the second power source unit by turning on the second switching unit by a voltage output from the first power source unit.