DEVICE FOR LIGHTING A DISCHARGE LAMP.

摘要

The inexpensive device having a soft-start function lights a discharge lamp by supplying the AC output of the self-excited half-bridge-type inverter to the lamp. In the inverter, two switching elements are alternately driven by the feedback from the secondary winding of a saturable current transformer. The impedance connected to the control winding of the saturable current transformer is increased for a predetermined period of time from the start of the lighting in order to control the current of the control winding. Further, the saturation time of the saturable current transformer is shortened to increase the output frequency and to decrease the output. Moreover, the impedance is increased if the input voltage is raised, in order to stabilize the output.