MDAC circuit for reducing mismatch error through channel randomization

Abstract

An MDAC circuit capable of reducing mismatch errors through channel randomization comprises a four-channel sampling switch capacitor array and an allowance amplifier module, in the sampling stage, one channel is randomly selected from the four-channel sampling switch capacitor array to sample input signals, the capacitor mismatch errors are averaged, and therefore, the influence of mismatching on the circuit is reduced. According to the invention, a plurality of sampling switch capacitor array channels are designed, and one channel is randomly selected to sample an input signal in each allowance amplifier working period, so that the effect of reducing capacitor mismatch errors is achieved, and the performance of the whole MDAC and analog-to-digital converter is further improved.

Description

technical field [0001] The invention relates to an MDAC design of a pipeline analog-to-digital converter, in particular to an MDAC circuit for reducing capacitance mismatch errors by channel randomization, and belongs to the field of analog-to-digital converters. Background technique [0002] In the design of the pipeline analog-to-digital converter, the MDAC circuit is usually implemented by a switched capacitor circuit. In the actual circuit, due to process deviations, etc., the capacitance value will deviate from the ideal value during the manufacturing process, which will affect the output of the MDAC, that is, the transmission of the MDAC. The curve will be affected by capacitance mismatch, causing MDAC output error, which affects the overall ADC linearity. Contents of the invention [0003] The purpose of the present invention is to overcome the disadvantages of the prior art, to provide an MDAC circuit with channel randomization to reduce capacitance mismatch errors...

AI Technical Summary

Problems solved by technology

[0002] In the design of the pipeline analog-to-digital converter, the MDAC circuit is usually implemented by a switched capacitor circuit. In the actual circuit, due to process deviations, etc., the capacitance value will deviate from the ideal value during the manufacturing process, which will affect the output of the MDAC, that is, the transmission of the MDAC. The curve will be affected by capacitance mismatch, resulting in MDAC output error, thus affecting the overall ADC linearity

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