Patent ID: 7466566
Filing Date: 2008-12-16
Classification: H02M,H05B,Y02B

Abstract:
1. A DC-AC converter, comprising: a transformer having a primary winding and at least one secondary winding; a first and a second semiconductor switches connected in series via said primary winding for allowing current to flow from a DC power source through said primary winding in a first direction; a third and a fourth semiconductor switches connected in series via said primary winding for allowing current to flow from said DC power source through said primary winding in a second direction; a current detection circuit for detecting the current that flows through a load connected to said secondary winding to thereby generate a current detection signal; a triangular wave signal generation circuit for generating a triangular wave signal; a PWM control signal generation circuit for generating a PWM control signal by comparing said triangular wave signal with an error signal generated on the basis of said current detection signal; an intermittent-operation control circuit adapted to a logic circuit that operates on the basis of said PWM control signal to generate a first simultaneously OFF period is established during which said first and fourth switches are simultaneously turned off, and a second simultaneously OFF period is established during which said third and second switches are simultaneously turned off, and that the direction of the current flowing through said primary winding is changed from one direction to the other when the magnitude of said current is zero.