| 摘要 |
PURPOSE:To attain low cost and circuit integration for a circuit by rectifying each output of plural preamplifiers with one rectifier circuit consisting mainly of transistors (TR). CONSTITUTION:A differential amplifier circuit 10 is formed with a differential amplifier circuit 10 and a TR group comprising TRs 6a-6n connected individually to preamplifiers 2a-2n. The collector of the TRs 6a-6n is connected in common to one output section of a current mirror circuit 16 and emitters of the TRs 6a-6n and the TR8 are connected in common to a constant current source 22. On the other hand, a constant current source 24 is connected to the other output part of the current mirror circuit 16, and a base of an emitter follower TR26 and a bias resistor 30 are connected to a connection section between the circuit 16 and the source 24 respectively. A smoothing circuit 32 is connected to the output section of a TR26. Only a capacitor 36 is mounted externally to a rectifier circuit 1 formed in this way and the other parts are formed as an IC. Thus, low cost and circuit integration are attained in this way. |
