| 摘要 |
PURPOSE:To reduce the consumption of electric power by increasing the voltage to be applied to the collector of a controlling transistor (TR) higher than the sum of voltage drop between the base and emitter of the controlling TR. CONSTITUTION:The voltage applied to a load 4 is supplied to each input terminal of an operational amplifier OP through a voltage dividing circuit consisting of a Zener diode ZD1 and resistors R1-R3 and the output of the operational amplifier OP controls the base potential of respective TRs Q1, Q2 to keep the voltage applied to the load 4 constant. At that time, voltage VA higher than the collector voltage of the power TR Q1 is applied to the collector of the controlling TR Q2 from the 2nd recrifying/smoothing circuit 7, so that the base current of the power TR Q1 can be supplied independently of the voltage VCE between the collector and emitter of the power TR Q1. |
