| 摘要 |
PURPOSE:To obtain a desired voltage gain with respect to an input voltage in which no clamp is implemented at its relevant output by varying a feedback quantity of a differential amplifier and a 1st clamp voltage setting voltage source fed to a base of a 1st transistor-(TR). CONSTITUTION:A differential amplifier consists of TRs 1, 3, a diode D1 and a TR 5, an emitter of a TR 6 is used as an output terminal and resistors R1, R2 form a feedback circuit. A base of the 1st TR 2 connects to a 1st clamp voltage setting voltage source VL and its collector connects to a reference side of the 2nd current mirror circuit, and a collector of the TR 4 forming the 2nd current mirror circuit with the diode D2 is connected to a collector of an inverting input TR 3. A half wave rectifier is formed by differential connection of TRs 7, 8 and an output of the differential amplifier connects to a base of a TR 7. Thus, a desired voltage gain is obtained within a range where no clamping is implemented. |
