| 摘要 |
PURPOSE:To provide the lighting device which effectively uses parts without degrading the function. CONSTITUTION:The AC power from a commercial AC power source E is subjected to full-wave rectfication by a full-wave rectifier 1, and the pulsating current is supplied to a chopper means 3. When a DC power source 2 is turned on, an inverter circuit 5 does not oscillate, and a light emitting diode LED is not lit, and a photo transistor PTr is in the turning-off state as it is. A thyristor Th1 is kept turned off, and the current flows through a resistance R1, and therefore, a rush current is reduced by the resistance R1. When the inverter circuit 5 is operated to light the light emitting diode LED, the phototransistor PTr is turned on, and the gate voltage is applied to the thyristor Th1, and the thyristor Th1 is turned on. The thyristor Thl by-passes the current of the resistance R1, and the thyristor Th1 of the chopper means 3 has the circulating function for boosting chopper. |
