A Multiple ResolutionA/D Converter Using for Wide Dynamic Range CMOS Image Sensors

Abstract

In this paper, we propose a method to expand a dynamic range usingdigital integration and a multiple resolution A/D converter. Short accumulated signals are read out for multiple times, and integrated with digital memory in order to reduce the SNR dip. To do this, a high-speed, high-resolution A/D converter is necessary at the column of the image sensor. The multiple-resolution A/D converter is suitable for the column parallel A/D converter. Simulation results show that the proposed approach has a sufficient SNR.