Single-stage AB-type operation transconductance amplifier and analog circuit

Abstract

The invention provides a single-stage AB-type operation transconductance amplifier and an analog circuit, and relates to the technical field of amplifiers. The AB-type input stage comprises a turnovervoltage follower and an input differential pair; the AB-type cross self-biased output stage comprises a first non-linear current mirror, a second non-linear current mirror and a cross self-biased circuit; two output ends of the turnover voltage follower are connected with the input differential pair through a first voltage maintaining node and a second voltage maintaining node; two input ends ofthe input differential pair are connected with input signals Vin+ and Vin-, and connected with the first non-linear current mirror; two output ends of the non-linear current mirror are crosswise connected with two input ends of the cross self-biased circuit; two output ends of the cross self-biased circuit are connected with the output ends Vo+ and Vo- of the amplifier; and the second non-linear current mirror is connected with the cross self-biased circuit. The single-stage AB-type operation transconductance amplifier is capable of effectively increasing the slew rate of the amplifier, and the maximum current output is not limited.

Description

technical field [0001] The invention relates to the technical field of amplifiers, in particular to a single-stage AB class operational transconductance amplifier and an analog circuit. Background technique [0002] In low-voltage and low-power switched capacitor circuits, especially when driving large capacitive loads, there is an increasing demand for operational transconductance amplifiers with high slew rates and large bandwidths. The current efficiency of the traditional folded cascode amplifier is low because it works in class A. The circuit structure of the traditional folded cascode amplifier is as follows: figure 1 shown. The input voltage enters from the gate of the input differential pair transistors M1 and M1N, and is converted into a drain output current, and then the input current is transmitted to the output terminal at the source of the common gate transistors M4 and M4N to generate an output voltage signal. M5, M6 and M5N, M6N are current source loads res...

AI Technical Summary

Problems solved by technology

[0003] The traditional current recovery technology can improve the current efficiency of the op amp, but the maximum output current of the current recovery technology is limited by the tail current of the input differential pair, so the slew rate can only increase linearly

Second, in conventional output stage structures, the common-gate transistors are biased by a constant voltage, so the maximum achievable output current is limited, especially in low-voltage applications

Therefore, the traditional folded cascode amplifier with current recovery has the following disadvantages: the slew rate can only be increased linearly and the maximum achievable output current is limited

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