Correcting circuit and correcting method for assembly line analog-digital converter based on zero-crossing comparison

Abstract

The invention belongs to the technical field of integrated circuits, and particularly relates to a correcting circuit and a correcting method for an assembly line analog-digital converter based on zero-crossing comparison. The correcting circuit provided by the invention is connected between two stages of circuits of the assembly line analog-digital converter based on zero-crossing comparison, and the correcting circuit comprises a difference 1 / f error amplifier, two capacitors for correction and two transmission gate circuits; each transmission gate circuit comprises an N-type field effect transistor and a P-type field effect transistor, and the channels of the N-type field effect transistor and the P-type field effect transistor are arranged in parallel. The correcting circuit is used for amplifying the error of the former stage of circuit and storing on the capacitors for correction, and then the error is compensated for output along with the setup process of the next stage of circuit. According to the correcting method provided by the invention, the conversion accuracy of the circuit can be effectively improved, meanwhile the conversion time longer than that of a traditional scheme is provided for sub-ADC (Analog to Digital Converter), and thus the speed requirement of a sub-ADC circuit can be reduced.

Description

technical field [0001] The invention belongs to the technical field of integrated circuits, and in particular relates to a pipeline analog-to-digital converter correction circuit and a correction method. Background technique [0002] Based on zero-crossing comparison, it is a popular solution to realize pipelined analog-to-digital converters in recent years. Its adjacent two-stage differential circuits are as follows: figure 1 shown. Similar to the traditional switched capacitor gain stage, the differential switched capacitor gain stage based on zero-crossing comparison realizes the processing of the differential signal with twice the overhead of the single-ended circuit. The symmetrical circuit structure of the upper and lower parts forms two positive and negative channels, which respectively process the positive input and negative input of the differential input signal, and obtain the final differential output result. figure 1 Mainly including the sampling capacitor C of...

AI Technical Summary

Problems solved by technology

[0004] According to the working process of the above circuit, when the zero-crossing comparator 100 cannot accurately jump at the zero-crossing moment, there will be a conversion error in the circuit

Images