Patent ID: 8189355

Claim:
A multiple-output switching power source apparatus comprising: a transformer having a primary winding, a first secondary winding, and a second secondary winding; a first control circuit to adjust a time for applying a DC voltage to the primary winding of the transformer by turning on/off a first switching element; a first rectifying-smoothing circuit to rectify and smooth a voltage generated by the first secondary winding of the transformer and provide a first output voltage; a second switching element whose first end is connected to an output terminal of the first rectifying-smoothing circuit; a second rectifying-smoothing circuit connected to a second end of the second switching element, to rectify and smooth a voltage generated at the second end of the second switching element and provide a second output voltage; a third rectifying-smoothing circuit to rectify and smooth a voltage generated at a second end of the second secondary winding of the transformer and provide a third output voltage, a first end of the second secondary winding of the transformer being connected to the second end of the second switching element; and a second control circuit to adjust an ON/OFF time of the second switching element according to the second and third output voltages.