Patent ID: 6061252
Filing Date: 2000-05-09
Classification: H02M

Abstract:
A switching power supply device having a series combination of a first switching circuit and an input power source connected in series with a series combination of a first winding of a transformer and an inductor, a series combination of a second switching circuit and a switched capacitor connected in parallel to a series combination of said first winding of the transformer and said inductor and further wherein a second winding of said transformer is provided with a rectifying smoothing circuit including a rectifying element,wherein said first switching circuit comprises a parallel connection circuit including a first switching element, a first diode, and a first capacitor,said second switching circuit comprises a parallel connection circuit including a second switching element, a second diode, and a second capacitor,and further comprising a switching controlling circuit adapted to turn said first and second switching elements on and off alternately with a period of time when both switching elements are off being interposed, anda capacitor being connected in parallel to said rectifying element in said rectifying smoothing circuit.