Rail-to-rail operational amplifier based on internal current inversion

Abstract

The invention provides a rail-to-rail operational amplifier based on internal current inversion. The rail-to-rail operational amplifier comprises a rail-to-rail input stage circuit, a current inversion circuit, a class A-B output stage circuit, a current mirror image circuit, an ascending current compensation circuit and a descending current compensation circuit, wherein the current mirror image circuit is used for providing bias current to the rail-to-rail input stage circuit, the current inversion circuit and the class A-B output stage circuit; the current inversion circuit is used for performing inversion processing on an output current signal of the rail-to-rail input stage circuit and providing the output current signal to the class A-B output stage circuit; the ascending current compensation circuit and the descending current compensation circuit are respectively used for compensating reduction, caused by input of complementary differential, of the working current of a tube during inputting of common mode level ascending or descending and are also used for compensating the working current of a class A-B output stage. The rail-to-rail operational amplifier based on internal current inversion has the advantages of rail-to-rail input and rail-to-rail output, is higher in working efficiency and output signal linearity and is lower in power consumption.

Description

technical field [0001] The invention relates to the technical field of integrated circuits, in particular to a rail-to-rail operational amplifier based on internal current inversion. Background technique [0002] In recent years, with the reduction of the feature size of the integrated circuit manufacturing process, the power supply voltage used has gradually decreased, but the threshold voltage of the device has not decreased accordingly, and the common-mode input / output range of the operational amplifier has become narrower and narrower, which is difficult to meet the current requirements. stage requirements. At the same time, in the fields of portable electronic devices, infrared focal plane readout circuits, LED drive circuits, flat panel display control circuits, etc., the requirements for low power consumption, high efficiency, and high speed of integrated circuit operational amplifiers are becoming more and more urgent. research goal. [0003] The rail-to-rail opera...

AI Technical Summary

Problems solved by technology

The shortcomings of this circuit are mainly manifested in the following two aspects: 1. The transconductance of the rail-to-rail input stage circuit changes greatly, and the harmonic distortion is relatively high; 2. The linearity of the output signal of the Class A and B output stage is reduced near the power supply and ground. Obvious, severely impact rail-to-rail input and output usage

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