Operational amplifier push-pull output stage with low quiescent

Details Operational amplifier push-pull output stage with low quiescent Operational amplifier push-pull output stage with low quiescent

1998-04-02

1999-10-26

Lee, Benny

Amplifiers

With semiconductor amplifying device

Including push-pull amplifier

330265, H03F 326

Patent

active

059735643

ABSTRACT:
An operational amplifier output circuit having a low, stable quiescent current includes an input stage (22) receiving an input voltage (v.sub.in ") and producing first (v.sub.1) and second (v.sub.2) signals. An output stage (23) includes a pull-up transistor (1) and a pull-down transistor (2), a base of the pull-up transistor (1) receiving the first signal (v.sub.1). An emitter of the pull-up transistor (1) is coupled by an output conductor (30) to a collector of the pull-down transistor (2). A base of the pull-down transistor is coupled to receive the second signal (v.sub.2), and an emitter of the pull-down transistor (2) is coupled to a second reference voltage conductor (GND). A feedback stage (24) includes a first sensing circuit (36) coupled to the pull-up transistor 1 and produces a third signal (v.sub.3) representing a collector current of the pull-up transistor (1), a second sensing circuit (37) coupled to the pull-down transistor (2) and producing a fourth signal (v.sub.4) representing a collector current of the pull-down transistor (2), a combining circuit (38) receiving the third (v.sub.3) and fourth (v.sub.4) signals to produce an error signal (v.sub.5) representing the larger of the third (v.sub.3) and fourth (v.sub.4) signals, and an error amplifier (17) receiving the error signal (v.sub.5) to produce a feedback signal (v.sub.6) regulating the first (v.sub.1) and second (v.sub.2) signals to establish a stable quiescent current in the pull-up transistor (1) or the pull-down transistor (2).

REFERENCES:
patent: 3983502 (1976-09-01), Wheatley, Jr.
patent: 4333059 (1982-06-01), Yamaguchi et al.
patent: 4403200 (1983-09-01), Davis
patent: 4521737 (1985-06-01), Bynum
patent: 4521740 (1985-06-01), Nakayama
patent: 4538116 (1985-08-01), Vyne
patent: 4833423 (1989-05-01), Molloy
patent: 4853645 (1989-08-01), Seevinck et al.
patent: 4857861 (1989-08-01), Seevinck et al.
patent: 4959623 (1990-09-01), Khoury
patent: 4990863 (1991-02-01), Susak et al.
patent: 5229721 (1993-07-01), Stade
patent: 5467058 (1995-11-01), Fujita
patent: 5592124 (1997-01-01), Mullins et al.
A 1-GHz Bipolar Class-AB Operational Amplifier with Multipath Nested Miller Compensation for 76-dB Gain, by Klaas-Jan de Langen et al., IEEE Journal of Solid State Circuits, Vol. 32, No. 4, Apr., 1997, pp. 488-498.

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