An inverting pseudo-fully differential amplifier with a common-mode feedback control circuit

Abstract

The invention discloses an inverting pseudo-full differential amplifier with a common-mode feedback control circuit and a method for keeping output common-mode level stable. The inverting pseudo-fulldifferential amplifier comprises a pseudo-full differential operational circuit and the common-mode feedback control circuit. The pseudo fully differential operational circuit includes inverter amplifiers (2) and (3), each of which has a first feedback control terminal and a second feedback control terminal. The input end of the common-mode feedback control circuit is respectively connected with the output ends of the inverter amplifiers (2) and (3); and the common-mode feedback control circuit is used for detecting common-mode output voltages of the inverter amplifiers (2) and (3), and the output end of the common-mode feedback control circuit is connected with the first feedback control terminal and the second feedback control terminal and used for forming common-mode feedback on the inverter amplifiers (2) and (3) so as to keep the common-mode output level stable. The a inverting pseudo fully differential amplifier can keep the stability of an output common-mode level in an application occasion with low voltage and low power consumption.

Description

technical field [0001] The invention relates to the field of low-voltage and low-power circuit design, in particular to an inverting pseudo full-differential amplifier with a common-mode feedback control circuit and a method for maintaining stable output common-mode levels. Background technique [0002] Fully differential amplifiers are widely used in high-precision analog circuit applications, such as data converters, sensor signal processing, and small signal processing. It has the characteristics of strong anti-interference ability and large signal swing. However, due to the deviation caused by the manufacturing of the devices, it is impossible to achieve 100% matching characteristics between the devices, making it difficult to determine the output common-mode level of the amplifier, which may cause the amplifier to enter the dead zone and greatly reduce the signal processing range. Therefore, the fully differential amplifier must have a common-mode feedback circuit to m...

AI Technical Summary

Problems solved by technology

In this application, the fully differential amplifier circuit and its common-mode feedback circuit cannot meet the application requirements of low voltage and low power consumption.

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