A High Dynamic Range CMOS Image Sensor with In-Pixel Floating-Node Analog Memory for Pixel Level Integration Time Control

Abstract

In this paper we report a high dynamic range CMOS image sensor (CIS) with in-pixel floating-node analog memory for pixel level integration time control. Each pixel has different integration time based upon the amount of its previous frame illumination. We can implement true CDS technique to reduce reset noise without any additional hardware because we use a floating-node parasitic capacitor as an analog memory. In the fabricated test sensor, we could achieve the extended dynamic range by more than 42dB. To the best of our knowledge, this is the first report on the use of pixel-node parasitic capacitor as an analog memory for the extension of dynamic range