Patent ID: 7385833

Claim:
A power converter having first and second input terminals where an input voltage is provided and first and second output terminals where the output DC voltage is provided, the converter comprising: a first inductor having a first number of winding turns and having one end connected to the first input terminal; a boost diode connected in series between the other end of said first inductor and said first output terminal; a first capacitor coupled across said first output terminal and said second output terminal; a switch alternately switched on and off as a function of a control signal for controlling current through said first inductor; said switch is connected between said second input terminal and a first node at the junction of said first inductor and said boost diode; and a snubber circuit comprising: a series combination of a second inductor magnetically coupled to said first inductor, a second diode and a third diode, said series combination connected across said output terminals; and, said second inductor having a second number of winding turns; and a resonant capacitor connected in series with said third diode between said first node and said first output terminal, wherein said second inductor and said resonant capacitor form a resonant circuit; and wherein said resonant capacitor's voltage is controlled at turn on of said switch as a function of the resonant action of said resonant circuit and the turns ratio of the windings of said first and second inductors.