| 摘要 |
PURPOSE:To prevent the malfunction of a stopping circuit at the time of abnormality in case of starting through the operation of a base current control circuit by deciding the output of the inverter device and stopping the operation of the abnormality stopping circuit when the starting through the operation of the base current control circuit. CONSTITUTION:When starting the inverter device 4 lighting a discharge lamp 13, the SCR29 of the base current control circuit 27 is brought to an OFF state, and base currents given to transistors 17, 18 from a drive circuit 23 are limited, and lit as normal base currents after a fixed time passes. The abnormality stopping circuit 33, which detects the abnormal voltage of the life terminating stage, etc. of the discharge lamp 13 by the detecting winding 11 of a transformer 12 and stops oscillation, is mounted while a control circuit 14 at the time of starting is connected between the circuit 33 and the drive circuit 23. Accordingly, output is determined, a transistor 43 is brought to an ON state and the operation of the abnormality stopping circuit 33 is stopped when starting, thus preventing malfunction, then improving reliability. |
