Patent ID: 7355867
Filing Date: 2008-04-08
Classification: G05F,H02M

Abstract:
1. A power supply that receives at least one alternating current (AC) input voltage and produces therefrom a DC output voltage, said power supply comprising: at least one rectifier that receives and rectifies the AC input voltage; a transformer comprising first and second windings, wherein the first winding is connected to receive the rectified input voltage so that current flows through said first winding, and wherein a voltage produced across the second winding defines the output voltage of the power supply; a first switching device, in electrical connection with the first winding, that controls the flow of current through the first winding to regulate the output voltage; a device for storing electrical charge connected in parallel with the first winding, the device for storing electrical charge also being connected to receive the rectified input voltage; a regulating device connected between the rectifier and the device for storing electrical charge, the first winding and the first switching device, the regulating device comprising a second switching device and a third switching device connected in series, wherein when the rectified input voltage exceeds a predetermined amount, the incremental amount of the rectified input voltage above the predetermined amount is applied to the second and third switching devices instead of the device for storing electrical charge, the first winding and the first switching device, thereby limiting the amount of the rectified input voltage applied to the device for storing electrical charge, the first winding and the first switching device to the predetermined amount; and circuitry connected between the rectifier and the device for storing electrical charge that limits the rate of rise and fall and the magnitude of current delivered by the rectifier to the device for storing electrical charge.