Patent ID: 8508959

Claim:
An image forming device comprising a two-voltage power supply including a transformer, a first output circuit to generate a first output voltage using a voltage transferred to a secondary winding of the transformer, and a first output voltage controller to control a voltage supplied to a primary winding of the transformer according to the first output voltage, the two-voltage power supply comprising: second output circuits to generate second output voltages using the voltage transferred to the secondary winding of the transformer; and second output voltage controllers to control linearly outputting the second output voltages by feeding back the second output voltages, wherein a second output circuit comprises: a second rectifier to generate a second output voltage by rectifying the voltage transferred from the transformer; and a second switch to linearly switch an output voltage of the second rectifier according to a linear control signal of a second output voltage controller, wherein the second switch comprises a transistor, and the second output voltage controllers apply the linear control signal to the second switch to allow the second switch to operate in an active region.