DISCHARGE LAMP LIGHTING DEVICE

摘要

PURPOSE:To provide circuit constitution by which an inverter can be controlled according to a load condition at load abnormal time such as the last stage of the service life of a discharge lamp or a no-load condition and which is suitable for downsizing in a discharge lamp lighting device by using push-pull inverter circuits having a constant current inductor. CONSTITUTION:In a discharge lamp lighting device by using pushpull inverter circuits Q1 and Q2 having a constant current inductor Ls, the device has a means to detect an electric current in the feedback winding arranged in the constant current inductor Ls. A control means is provided to restrict output of the inverter circuits when an abnormal electric current the circuits at load abnormal time such as the last stage of the service life of a discharge lamp 1 or a no-load condition is detected.