| 摘要 |
PURPOSE:To generate a large voltage against such a large current as a short circuit current, and to maintain a reverse bias action by providing with a means which does not output an ON-signal to a switch device, when a switching means is ON. CONSTITUTION:When a switch 6 is turned on, and a large power source short circuited current flows through a transistor 3 and the switch 6, a large voltage drop is generated in a current limiting means 4, and a large base reverse bias voltage is impressed to its emitter junction. Also, even if a load current flows between terminals 12, 13 during an ON-period of the switch 6, its current is smaller than the power source short circuited current, and only a small voltage drop is generated in the means 4, therefore, an energy loss by the means 4 is small. In such a way, as keeping a large reverse bias voltage maintaining, the energy loss can be decreased. |
