One-step three-bit successive approximation type analog-to-digital converter

Abstract

The invention belongs to the field of digital-to-analog conversion, in particular to a one-step three-bit successive approximation type analog-to-digital converter. The converter comprises a first bootstrap switch, a second bootstrap switch, a signal capacitator array, a comparator group, a control logic circuit, a register unit, and a pseudo asynchronous clock generation unit. The first bootstrap switch is arranged between an analog signal input end and a signal capacitor array. The second bootstrap switch is arranged between a reference voltage input end and a reference capacitor array, and the output end of the signal capacitor array and the output end of the reference capacitor array are connected with the first input end and the second input end of the comparator set respectively.A first output end of the comparator group is connected with an input end of the control logic circuit. A first control signal output end and a second control signal output end of the control logic circuit are respectively connected with a control signal input end of the signal capacitor array and a control signal input end of the reference capacitor array. The register unit is arranged between the result output end of the control logic circuit and the signal input end of the decoder. The pseudo asynchronous clock generation unit obtains a comparison result of the comparator group and providesa clock signal for the comparator. The analog-to-digital conversion rate can be improved.

Description

technical field [0001] The invention belongs to the field of digital-to-analog conversion, and in particular relates to a one-step three-bit successive approximation analog-to-digital converter. Background technique [0002] Successive approximation analog-to-digital converter (SAR ADC, successive approximation register Analog to Digital), in each conversion process, by traversing all quantized values ​​and converting them into analog values, comparing the input signal with it one by one, and finally getting the desired output digital signal. Due to the advantages of simple structure and low power consumption of successive approximation analog-to-digital converters, successive approximation analog-to-digital converters are widely used in fields with low power consumption requirements such as wearable devices and medical devices. [0003] High-speed communication systems, such as ultra-wideband, optical communication, etc., require ADCs with low-to-medium resolution and samp...

AI Technical Summary

Problems solved by technology

However, limited by the structure of a single comparator, the traditional successive approximation analog-to-digital converter can only quantize one bit of digital code in each comparison cycle, which is called a step-by-bit successive approximation analog-to-digital converter. In this way, an N A bit-accurate successive-approximation ADC requires at least N comparison cycles, so the conversion rate is very limited

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