Analog-to-Digital Converters and Image Sensors

Abstract

An analog-to-digital converter and an image sensor. The analog-to-digital converter includes: a comparison module, adapted to compare the voltage of a pixel bit line with N threshold voltages respectively, determine the interval in which the voltage of the pixel bit line is located, and determine the voltage of the pixel bit line After the interval of the voltage, the comparison module is suitable for comparing the voltage of the pixel bit line with the slope voltage to generate a comparison result; the counter control module is suitable for N+1 different counters according to the interval of the voltage of the pixel bit line In the enable signal, select the target enable signal corresponding to the interval where the pixel bit line voltage is located, wherein the counter starts counting when the target enable signal enters the enable phase, and the voltage range of the ramp voltage in the enable phase is N+1 part of the intervals, and cover the interval where the pixel bit line voltage is; the counter inputs the comparison result, and when the comparison result is reversed, the counter ends timing. By adopting the above solution, the power consumption of the counter can be reduced.

Description

technical field [0001] Embodiments of the present invention relate to the technical field of image sensors, and in particular, to an analog-to-digital converter and an image sensor. Background technique [0002] A column-parallel analog-to-digital converter (Analog-to-Digital Converter, ADC) has become a mainstream architecture of a Complementary Metal Oxide Semiconductor (Complementary Metal Oxide Semiconductor, CMOS) image sensor. A CMOS image sensor includes a plurality of column-parallel ADCs, and in a pixel array of the image sensor, each column of ADCs processes each column or several columns of pixels respectively. [0003] Each column of ADCs consists of amplifiers, comparators, and counters. The power consumption of the counter is related to the brightness of the image. The greater the brightness of the image, the longer the counting time of the counter, and the greater the power consumption of the counter, resulting in a large amount of heat generated by the image...

AI Technical Summary

Problems solved by technology

The power consumption of the counter is related to the brightness of the image. The greater the brightness of the image, the longer the counting time of the counter, and the greater the power consumption of the counter, which will cause the image sensor to generate more heat

When the image sensor heats up a lot, the image quality is lower

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