| 摘要 |
An object of the present invention is to provide a lighting device for a discharge tube which is stably operated at high frequency and is small and inexpensive. AC voltage is applied to a resonant unit provided with an inductor (Lr) and a capacitor (Cr). AC current a supplied to a discharge tube (16) connected to any one of the inductor (Lr) and the capacitor (Cr) according to the switching operation of the two power semiconductor elements (Q1, Q2) connected in a bridge manner. The resonant unit and first and second voltage drop units (Z1, Z2) connected in series between I/O terminals of the bridge and the voltages of the first and the second voltage drop units are applied as a signal of opposite phases to a control terminals of the two power semiconductor elements, thereby to guarantee the stable resonant operation in synchronous to the high-frequency load current in the lighting device for illumination. <IMAGE> |
