Patent ID: 8085558
Filing Date: 2011-12-27
Classification: H02M,Y02B

Abstract:
1. A resonant converter comprising: a square wave generator including a first primary-side switch and a second primary-side switch that are coupled to a primary coil of a transformer, and generating a first square wave corresponding to an input voltage by alternately turning on/off the first primary-side switch and the second primary-side switch; a resonator including a first coil of the primary coil of the transformer, and generating a resonance waveform corresponding to the first square wave; and an output unit including a second coil of a secondary coil of the transformer, and outputting an output voltage corresponding to a current that is generated in the second coil corresponding to the resonance waveform, and wherein the square wave generator includes a pulse frequency modulation controller for (i) turning on/off the first primary-side switch and the second primary-side switch, (ii) comparing, at the time when the second primary-side switch is turned off, a rising voltage that is linearly increased while the second primary-side switch maintains the turn-on state and an integrated voltage corresponding to an integrated value, integrated over a time of the current flowing to the second primary-side switch, and (iii) changing on/off drive frequencies of the first primary-side switch and the second primary-side switch according to a result of the comparison.