12-bit intermediate-rate successive approximation type analog-digital converter

Abstract

The invention provides a 12-bit intermediate-rate successive approximation type analog-digital converter and relates to the field of analog-digital converters. The 12-bit intermediate-rate successive approximation type analog-digital converter comprises a sampling network, a differential capacitor array connected with the sampling network, and a comparator circuit connected with the differential capacitor array, wherein the differential capacitor array comprises a first capacitor array connected with the positive-phase input end of the comparator circuit, and a second capacitor array connected with the negative-phase input end of the comparator circuit; both the first capacitor array and the second capacitor array are composed of 11 groups of binary-structured bit capacitors, and the bottom plates of the redundant capacitors of the second capacitor array are constantly connected with a common-mode voltage VCM. The 12-bit intermediate-rate successive approximation type analog-digital converter solves the problems of large capacitor area and high power consumption of a traditional binary capacitor type structure.

Description

technical field [0001] The invention relates to the field of analog-to-digital converters, in particular to a 12-bit medium-rate successive approximation analog-to-digital converter. Background technique [0002] Successive approximation analog-to-digital converter (SAR ADC) is a type used in medium precision and medium sampling rate, and is widely used in various medical, portable and communication systems because of its simple structure, small area, and high power utilization . Since the successive approximation analog-to-digital converter does not require linear gain blocks such as operational amplifiers, the SAR ADC can better adapt to the technological evolution trend of reduced feature size and lower power supply voltage. With the advancement of technology, the conversion rate that SAR ADC can achieve has also increased to hundreds of megabytes, which can be compared with pipeline analog-to-digital converters, and has higher power consumption utilization. [0003] Th...

AI Technical Summary

Problems solved by technology

However, since the precision of the analog-to-digital converter reaches 12 bits, the total capacitance area of ​​the traditional binary capacitive structure is too large, and the power consumption is also large

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