Patent ID: 9385615
Filing Date: 2016-07-05
CPC Classification: H02M,Y02B

Claim Text:
1. An isolated switching power supply comprising: a switching element that is connected to an input power supply through a primary winding of an isolation transformer; a control circuit that ON/OFF-drives the switching element and generates an AC power in a secondary winding and in an auxiliary winding of the transformer; an output circuit that rectifies the AC power generated in the secondary winding of the isolation transformer and outputs the rectified power; an internal power supply circuit that generates a driving power supply voltage for the control circuit from the AC power generated in the auxiliary winding of the transformer; an output voltage detecting circuit that feeds back an output monitoring voltage derived from the driving power supply voltage generated by the internal power supply circuit to the control circuit to control the ON/OFF driving of the switching element by the control circuit; and an output voltage controller that changes a level of the output monitoring voltage obtained from the driving power supply voltage corresponding to a change of a condition for the ON/OFF driving of the switching element in the control circuit, wherein a change of a condition signal is received at the output voltage controller directly from the control circuit.