DISCHARGE LAMP LIGHTING DEVICE

摘要

PURPOSE:To normally light a discharge lamp with a stable resonance condition realized by properly controlling an off-action of a switching element of an inverter circuit. CONSTITUTION:A commercial power supply AC is rectified by a full wave rectification circuit DB to be a pulsating voltage to become a lighting voltage at an inverter such as an inductor L1 or a capacitor C1 to light a discharge lamp Z. On/off of a transistor(TR)Q1 of the switching element of the inverter are controlled by a control circuit, so it is off when the pulsating voltage is low, while it is on in a section where the pulsating voltage is not in a normal direction. An unnecessary stress applied to the TRQ1 is thus eliminated, thereby action of the inverter is stabilized to light the discharge lamp normally even in the case of using the pulsating voltage.