Patent ID: 7907424
Filing Date: 2011-03-15
Classification: H02M

Abstract:
1. A power supply device having zero switching voltage, comprising: a first switch, said first switch being a three-end element and comprising a parasitic body diode, having a first end coupled to one end of a first input voltage (V a first capacitor, said first capacitor having opposing first and second ends thereof respectively coupled to the first and third ends of said first switch; an inductor, said inductor having one end thereof coupled to the third end of said first switch; a transformer, said transformer comprising a primary side, a secondary side, a first winding at said primary side, and a second winding and a third winding at said secondary side; a second switch, said second switch being a three-end element and comprising a parasitic body diode, having a first end coupled to an opposite end of said input voltage (V a second capacitor, said second capacitor having opposing first and second ends thereof respectively coupled to the first and third ends of said second switch; a first voltage output unit, said first voltage output unit providing a first voltage output; and a second voltage output unit, said second voltage output unit comprising a third switch and providing a second voltage output; wherein by means of controlling the order in which said first switch, said second switch and said third switch are to be switched on, switching voltage is eliminated from said first switch and said second switch; wherein said second voltage output unit comprises: