voltage follower circuit

Abstract

The present invention relates to a voltage following circuit. The voltage following circuit includes: an offset calibration circuit and a programmable operational amplifier; the offset calibration circuit compares the voltage of the first input terminal and the voltage of the second input terminal of the programmable operational amplifier, and outputs an adjustment signal according to the comparison result; The programmable operational amplifier adjusts the voltage of the second input terminal of the programmable operational amplifier according to the adjustment signal to reduce the mismatch voltage of the programmable operational amplifier.

Description

technical field [0001] The invention relates to the technical field of circuits, in particular to a voltage follower circuit. Background technique [0002] With the development of circuit technology, complementary metal oxide semiconductor (ComplementaryMetalOxideSemiconductor, CMOS) circuits are becoming more and more popular. The reasons are: 1. The CMOS process is easy to continuously reduce the size, so that the circuit area under the CMOS process is easy to decrease with the process size. Small and reduced, which has the advantage of lower cost; Second, compared with bipolar devices, CMOS devices have a lower gate input current, which can usually be ignored, while bipolar devices require a larger The base current is unfavorable for low power consumption circuit applications. However, compared with bipolar circuits, CMOS circuits have a larger offset voltage. Generally, the mismatch voltage of CMOS devices is as high as 10mV to 50mV, while the mismatch voltage of bipola...

AI Technical Summary

Problems solved by technology

[0002] With the development of circuit technology, complementary metal oxide semiconductor (ComplementaryMetalOxideSemiconductor, CMOS) circuits are becoming more and more popular. The reasons are: 1. The CMOS process is easy to continuously reduce the size, so that the circuit area under the CMOS process is easy to decrease with the process size. Small and reduced, which has the advantage of lower cost; Second, compared with bipolar devices, CMOS devices have a lower gate input current, which can usually be ignored, while bipolar devices require a larger base current, which is not good for low-power circuit applications

However, compared with bipolar circuits, CMOS circuits have a larger offset voltage. Usually, the mismatch voltage of CMOS devices is as high as 10mV to 50mV, while the mismatch voltage of bipolar devices is only 1mV to 5mV.

Images