| 摘要 |
PURPOSE:To widen input and output dynamic range and to reduce the number of circuit elements by adding transistors to an amplifier circuit provided with a differential amplifier and a PP amplifier circuit. CONSTITUTION:Output V0 of the differential amplifier 11 drives a transistor TRQ15 that forms the PP amplifier circuit 12. Emitter current of the TRQ15 is supplied in common as base current of added TRQ16 and TRQ17. Voltage between base and emitter of the TRQ16 and forward voltage of a diode Q19 are impressed between bases of TRQ17, Q18. By adding this TRQ16, input dynamic range of the differential amplifier 11 can be enlarged without enlarging idling current of the PP circui 12. By utilizing between the base and emitter of the TRQ16, output dynamic range can be enlarged and the number of circuit elements can be reduced. |
