Starter circuit configuration for a discharge lamp lighting circuit

摘要

A discharge lamp lighting circuit 1 has a starter circuit 5 for superposing a start signal to a discharge lamp 6 on AC voltage of a DC-AC conversion circuit 4 and applying to the discharge lamp 6. When a diode D1 conducts, a capacitor C2 placed at the output stage of a DC power supply circuit 3 is charged. When a diode D2 conducts, the charges accumulated in the capacitor D2 are transferred to a capacitor D3. As the charges are transferred from the capacitor C3 to a capacitor C1, the terminal voltage of the capacitor C1 is raised, then when the voltage finally reaches a sufficient voltage value for a switch element SWg to conduct (or break down), pulse voltage is generated in a primary circuit 10 of a transformer ST and is applied to the discharge lamp 6 through a secondary winding STb of the transformer ST.