Patent ID: 7889526
Filing Date: 2011-02-15
Classification: H02M,H05B

Abstract:
1. A cat-ear power supply for a load control device for controlling the amount of power delivered to an electrical load from an AC power source, the power supply operable to generate a DC voltage, the power supply comprising: an energy storage capacitor; a controllably conductive switching circuit coupled in series electrical connection with the energy storage capacitor for selectively charging the energy storage capacitor to produce the DC voltage, the controllably conductive switching circuit operable to become conductive to charge the energy storage capacitor near the beginning of a half-cycle of the AC power source; a latch circuit coupled to the controllably conductive switching circuit, wherein the latch circuit controls the controllably conductive switching circuit to be non-conductive in response to the magnitude of the DC voltage; and a switch voltage monitor circuit coupled to the controllably conductive switching circuit and the latch circuit, such that the switch voltage monitor circuit controls the controllably conductive switching circuit to be non-conductive when the magnitude of a switch voltage across the controllably conductive switching circuit exceeds a predetermined switch voltage threshold and also resets the latch circuit when the magnitude of the switch voltage exceeds the predetermined switch voltage threshold; wherein the controllably conductive switching circuit is operable to become conductive to charge the energy storage capacitor near the end of the half-cycle when the magnitude of the switch voltage drops below the predetermined switch voltage threshold.