| 摘要 |
PURPOSE:To set highly accurately an output DC potential of a differential amplifier circuit by providing plural transistor (TR) of cascode connection and diodes to a current path connecting a current mirror circuit and a bias circuit. CONSTITUTION:TRs 27-32 and diodes 33, 34 are connected in sascode between an input TR12 for input forming the current mirror circuit and a TR14 forming a bias current circuit. A bias voltage equal to a DC input bias voltage of TRs 1, 2 forming the differential amplifier circuit is impressed to bases of the TRs 27-32. Thus, the deviation of a DC output potential VoutDC caused by the collector current of TRs 1, 2, 19, 20, 22, 27 decreased than the emitter current by the base current's share is compensated. Then the output DC potential of the differentil amplifier circuit is set highly accurately. |
