Patent ID: 6927989
Filing Date: 2005-08-09
Classification: H02M,H05B,Y02B

Abstract:
1. A DC-AC converter comprising: a transformer having a primary winding and at least one secondary winding; a semiconductor switching circuit which allows a current from a DC power source to flow in first and second directions through said primary winding; a current detecting circuit which detects a current flowing through a load connected to said secondary winding; a triangular signal generating section which generates a triangular signal; a PWM control signal generating section which compares an error signal due to a current detection signal output from said current detecting circuit, with said triangular signal to generate a PWM control signal; an intermittent operation triangular signal generating section which includes an intermittent operation triangular signal oscillator circuit and an intermittent operation capacitor, and which generates an intermittent operation triangular signal; a comparing section which compares said intermittent operation triangular signal with a continuous duty signal to generate an intermittent operation signal; and an intermittent operation controlling section which, when an intermittent operation is turned OFF, sets said error signal to substantially zero on the basis of said intermittent operation signal; wherein said semiconductor switching circuit is switched in accordance with said PWM control signal.