Successive approximation register analog-to-digital converter, CMOS image sensor including the same and operating method thereof

摘要

A complementary metal oxide semiconductor (CMOS) image sensor includes a pixel array suitable for outputting a pixel signal corresponding to incident light; a row decoder suitable for selecting and controlling pixels in the pixel array by row lines; a tracking voltage generator suitable for generating a tracking voltage; a plurality of successive approximation register (SAR) analog-to-digital converters suitable for analog-to-digital converting a pixel signal by repeatedly performing N times (where N is a natural number representing desired resolution) a process of comparing the pixel signal generated by the pixel array with the tracking voltage generated by the tracking voltage generator and modulating the pixel signal; and a control unit suitable for controlling operations of the row decoder, the tracking voltage generator, and the plurality of SAR analog-to-digital converters.