Patent ID: 7433209
Filing Date: 2008-10-07
Classification: H02M,Y02B

Abstract:
1. A soft-switching DC/DC converter, comprising: a converter circuit comprising a main switch having a first, a second and a control terminals for converting an input DC voltage to an output DC voltage; a resonant circuit comprising a secondary winding of a transformer having a first and a second terminals, a resonant inductor having a first and a second terminals, a resonant diode having an anode and a cathode and a flywheel diode having an anode and a cathode, wherein said first terminal of said secondary winding is electrically connected to said cathode of said flywheel diode and said first terminal of said resonant inductor, said second terminal of said secondary winding is electrically connected to said cathode of said resonant diode, said second terminal of said resonant inductor is electrically connected to said converter circuit, and said anode of said resonant diode is electrically connected to said anode of said flywheel diode and said converter circuit; and an energy transferring circuit comprising an auxiliary switch having a first, a second and a control terminals and magnetically coupled to said resonant circuit, wherein said main switch is turned on under a specific voltage across said first and said second terminals of said main switch and said auxiliary switch is turned off under a specific current flowing through said first and said second terminals of said auxiliary switch both controlled by said resonant circuit through a resonance effect so as to accomplish a soft-switching of said converter.