| 摘要 |
PURPOSE:To reduce the loss of a main transistor by inhibiting the supply of a base current of the transistor until the voltage between the collector and the emitter of the transistor crosses zero. CONSTITUTION:A series circuit of a capacitor 71 and a diode array 2 is connected with between both terminals of feedback winding 31f of an output transformer 31 so that diode array 72 becomes the same polarity as the base and the emitter of a main transistor 32, and a transistor 73 is connected in series with the base drive circuit of the transistor 32. A drive controller having a transistor 74 and diodes 75, 76 for turning ON the transistor 73 only when the array 72 generates a positive voltage is provided. |
