| 摘要 |
PURPOSE:To decrease the minimum operating voltage and also to obtain an excellent voltage current converting characteristic excellent over a board range by connecting in parallel a diode to a current feedback resistor connected between an emitter and a power supply of transistors (TRs) of current mirror connection. CONSTITUTION:The impedance of the diodes D1, D2 is high at a minute operating current, the current feedback is performed mainly by resistors R1, R2 to obtain a normal current converting characteristic, and a collector current of transistors (TRs) Q1, Q2 flows almost to the diodes D1, D2 at a large operating current and the current feedback is applied together with the resistors R1 and R2. Since the voltage drop by the resistors R1, R2 is limited respectively by the diodes D1 and D2 connected in parallel in this case, the minimum operating power is reduced and the circuit acts at a broad power supply voltage range. The characteristic at the large current is not remarkably deteriorated by making the characteristics of the diodes D1, D2 and the TRs Q1, Q2 identical to each other. |
