| 摘要 |
The invention proposes a push-pull symmetrical amplifier, in which the first n-p-n and the second р-n-р bipolar transistors in connection with twenty third р-n-р and twenty fourth n-p-n bipolar transistors compose push-pull symmetrical input circuit. The first of p-type and the second of n-type field-effect transistors in cascade connection provide mode of automatic assignment of the operational point and substantially increase output resistance of amplifier cascades that bring to accuracy in scheme work in the case of supply voltage changing and increasing amplification of the scheme. A current source, fifth to tenth bipolar transistors and also twenty first and twenty second transistors form scheme of DC mode setting of device cascade. Current reflectors built on the third, the fourth, the eleventh, the thirteenth, the fourteenth bipolar transistors provide bias current of paraphrase current reflectors made on the twelfth, the thirteenth, the seventeenth, the eighteenth, twenty fifth, twenty sixth bipolar transistor. Bipolar transistor seventh-twentieth are form push-pull symmetrical output circuit. Balancing capacitor corrects amplitude-frequency characteristic AND prevent generating, feedback resistor is set the gain. |
