ANALOG-TO-DIGITAL CONVERTER AND CMOS IMAGE SENSOR WITH THE SAME AND METHOD OF OPERATING CMOS IMAGE SENSOR

摘要

An analog-to-digital converter includes a comparator, a latch, and a bias control unit. The comparator is turned on by an applied bias voltage for comparing an analog voltage with a ramp voltage. The latch activates an end signal when the ramp voltage becomes greater than the analog voltage as indicated by the comparator. The bias control unit uncouples the bias voltage from the comparator when the end signal is activated for reducing power consumption.