| 摘要 |
PURPOSE:To prevent breakage of a switching element of an inverter circuit and its drive circuit in starting a discharge lamp. CONSTITUTION:When starting a discharge lamp, a start pulse is generated only in a period in which an inverter circuit 2 get on with FET 21, 24, and generation of the start pulse is stopped in a period in which FET 22, 23 get on to provide a stop period. An energy to be generated at a secondary winding of a pulse transformer 41 in the start pulse generating period is thus generated by charging an output capacitor of a DC power supply circuit 1. Increase of an input voltage of the inverter circuit 2, thus, can be restricted. |
