A 105.6dB DR and 65dB peak SNR self-reset CMOS image sensor using a Schmitt trigger circuit

A self-reset pixel level CMOS image sensor (CIS) is designed and tested which provides simultaneous improvements in dynamic-range (DR) and SNR performances. The pixel is fabricated in 0.5-µm 3-metal 2-poly CMOS technology and resulted in DR of 105.6dB with 65dB of peak SNR improvements. A simple Schmitt trigger circuit with offset cancellation technique is utilized to achieve this performance which compensates for the reset offset, comparator offset and reset delay.