Patent ID: 6680584
Filing Date: 2004-01-20
Classification: H05B

Abstract:
An electric-discharge lamp lighting apparatus, comprising:a first transformer, having both a primary winding connected with a direct-current power source and a secondary winding, for rising up a voltage, which is generated in the primary winding, in the secondary winding; a second transformer, having both a primary winding connected with the direct-current power source and a secondary winding, for rising up a voltage, which is generated in the primary winding, in the secondary winding; an electric-discharge voltage applying circuit for applying the voltage generated in the first transformer or the second transformer to an electric-discharge lamp through a high voltage generating circuit; a first switching circuit for performing an on-off control to pass or intercept a voltage applied to the first transformer; a second switching circuit for performing an on-off control to pass or intercept a voltage applied to the second transformer; a referential rectangular wave generating circuit for generating a referential rectangular wave; an inverting circuit for inverting the referential rectangular wave generated in the referential rectangular wave generating circuit; a first integrating circuit for integrating a level of the referential rectangular wave generated in the referential rectangular wave generating circuit and producing a chopping wave; a second integrating circuit for integrating a level of a rectangular wave inverted in the inverting circuit and producing a chopping wave; a first comparing circuit for comparing a level of the chopping wave produced in the first integrating circuit and a feed-back voltage sent from a feed-back circuit and outputting a control signal to the first switching circuit; and a second comparing circuit for comparing a level of the chopping wave produced in the second integrating circuit and the feed-back voltage sent from the feed-back circuit and outputting a control signal to the second switching circuit.