Patent ID: 8198874
Filing Date: 2012-06-12
Classification: H02M

Abstract:
1. A switched-power circuit, comprising: a magnetic coupling element for coupling an input of the switched-power circuit to an output of the switched-power circuit and having at least one winding; a switching circuit for controlling energizing of a primary winding of the magnetic coupling element from an input voltage source connected to the input of the switched-power circuit; a current sensing transformer having a primary winding coupled in series with the at least one winding of the magnetic coupling element and the switching circuit, and having a secondary winding; a control circuit for controlling switching of the switching circuit; a current sensing circuit coupled to the secondary winding of the current sensing transformer for providing an indication of a magnitude of current conducted through the at least one winding of the magnetic coupling element; and an auxiliary power supply having an input coupled to the secondary winding of the current sensing transformer and an output coupled to the control circuit for providing a supply voltage to the control circuit.