Successive approximation analog-to-digital converter and its digital calibration method and device

Abstract

The invention discloses a successive approximation analog-to-digital converter and a digital calibration method and device thereof. The method comprises the following steps: carrying out heat treatment; sequentially obtaining calibration codes of the conversion bits corresponding to the capacitors to be calibrated from the highest conversion bit of the conversion bit corresponding to the capacitors to be calibrated to the low conversion bit; according to a normal successive approximation mode, converting an input analog signal to obtain a binary conversion value, and calculating the sum of thecalibration codes of the conversion bits corresponding to the conversion value of 1 in the binary conversion value; and calculating a difference value between the binary conversion value and the sumof the calibration codes of which the conversion value in quasi-transposition corresponding to the capacitor to be calibrated is 1, so as to obtain the conversion value of the verified ADC. The methodcan effectively calibrate the mismatch error between the capacitors caused by the parasitic capacitance and the process manufacturing error, and avoid the problem that the double relation between thecapacitors is inaccurate due to the mismatch error, thereby effectively improving the precision of the ADC.

Description

technical field [0001] The present invention relates to the technical field of analog-to-digital conversion, in particular to a digital calibration method for successive approximation analog-to-digital converters, a non-transitory computer-readable storage medium, and a digital calibration method for successive approximation analog-to-digital converters. device and a successive approximation analog-to-digital converter with the device. Background technique [0002] As a bridge connecting analog signals and digital signals, analog-to-digital converters are developing rapidly in integrated circuits and information industries. The comprehensive advantages of conversion speed, low power consumption and low cost have been widely used. Usually, SARADC is mainly composed of digital-to-analog converter (DAC), comparator, digital control part and other analog circuits, and its core is DAC, comparator and digital control part. [0003] As one of the key units of the charge redistrib...

AI Technical Summary

Problems solved by technology

For this reason, the first purpose of the present invention is to propose a digital calibration method for successive approximation analog-to-digital converters, which can effectively calibrate the mismatch error between capacitances caused by parasitic capacitances and process manufacturing errors, and avoid Mismatch errors cause inaccurate doubling of the relationship between capacitors, which can effectively improve the accuracy of the ADC

Images