| 摘要 |
PURPOSE:To increase the design latitude, and reduce the cost by providing a control element for changing a control current value on the output side of a control winding of a saturable current transformer for controlling an output of an inverter. CONSTITUTION:An inverter 15 performs self-oscillation by a saturable current transformer CT1, and supplies a high frequency output to a discharge lamp FL. In this case, a control element Q3 is provided on the output side of a control winding CT1d of the saturable current transformer CT1, a lighting detecting circuit 18 detects an EL lighting of the discharge lamp, this control element Q3 is controlled to send a large current before lighting of the discharge lamp FL, and it is control led to send a small current after lighting of the discharge lamp FL. The design freeness is thus increased, and the cost came be reduced. |
