Patent ID: 10159125

Abstract:
An LED power supply device includes a primary winding, a secondary winding, a charge-pump capacitor, a bridge rectifier circuit, a unidirectional controlled switch, and an output capacitor. The secondary winding includes a first terminal and a second terminal and configured to provide a secondary current in response to a primary current flowing through the primary winding. A first terminal of the charge-pump capacitor is coupled to the second terminal of the secondary winding. The bridge rectifier circuit is coupled to the first terminal of the secondary winding and a second terminal of the charge-pump capacitor. The unidirectional controlled switch is reversely coupled to one of multiple diodes in the bridge rectifier circuit, and configured to be on or off according to a control voltage selectively. The output capacitor is coupled to the bridge rectifier circuit and configured to provide an output voltage according to the secondary current.