Patent ID: 7095631
Filing Date: 2006-08-22
Classification: H02M

Abstract:
1. A switching power converter for receiving an AC power and then outputting a DC power, the converter comprising: a transformer comprising a primary side coil and a secondary side coil, wherein the primary side coil, according to the AC power, generates an induced voltage at the secondary side coil; a charge storage unit coupled to the secondary side coil, wherein the charge unit is charged by the induced voltage and then outputs the DC power; a synchronization signal generator generating a synchronization signal according to the induced voltage, wherein when the induced voltage is positive, the synchronization signal is a first value and when the induced voltage is negative, the synchronization signal is a second value; a switch controller generating a control signal according to the synchronization signal, wherein when the synchronization signal is changed from the second value to the first value, the control signal is changed to a first control value, and after a predetermined period of time, the control signal is changed to a second control value; and a switch element serially connected to the secondary side coil and controlled by the control signal, wherein when the control signal is the first control value, the switch element is turned on and when the control signal is the second control value the switch element is turned off.