| 摘要 |
PURPOSE:To obtain a stabilized output voltage, by providing a control transistor which has connected the emitter to a connection point of a Zener diode and a resistance, has connected the base to a voltage division point of a series circuit of the resistance, and has connected the collector to the base of said transistor. CONSTITUTION:The emitter of a transistor TRQ1 is connected to an electric power source B through a switch S, a load L is connected to the collector of said TRQ1, a series circuit of a Zener diode ZD1 and a resistance is connected in parallel with the load L, and the emitter of a control TRQ4 is connected to a connection point of the diode ZD1 and the resistance 14. The collector of the TRQ4 is connected to the base of the TRQ1 through a resistance 13. Also, the base of the TRQ4 is connected to a connection point of resistance R11, R12 so as to be in parllel with the load L, and a resistance 15 is connected between the emitter and the collector of the TRQ1. In this case, stabilized output voltage Vout is applied to the diode ZD1, therefore, even if input voltage Vin is varied, a flowing current is scarcely varied. |
