Patent ID: 6396717
Filing Date: 2002-05-28
Classification: H02M,Y02B,Y02P

Abstract:
A switching power supply circuit comprising:.voltage doubler rectifier means including a first pair of rectifier diodes connected in series, a second pair of diodes connected in series and connected via a coil in parallel with said first pair of rectifier diodes and a pair of smoothing capacitors connected in series for performing voltage doubler rectifier operation on an alternating-current input voltage; switching means including a switching device for interrupting a doubled direct-current voltage from said voltage doubler rectifier means; an isolating converter transformer including a primary winding, a secondary winding, and a tertiary winding for coupling a switching output fed to said primary winding from said switching means to said secondary winding and said tertiary winding; primary-side resonant means formed by at least a leakage inductance component of the primary winding of said isolating converter transformer and a capacitance of a primary-side parallel resonant capacitor for converting operation of said switching means into voltage resonance; and feedback means for feeding back a switching output voltage transmitted to said tertiary winding to said second pair of diodes connected in series.