A novel CMOS image sensor using an output voltage feedback with variable dynamic range

In this study, we propose a new complementary metal-oxide semiconductor (CMOS) image sensor to extend the dynamic range. The proposed active pixel sensor (APS) uses a gate/body-tied PMOSFET-type (GBT) photodetector and an output voltage feedback structure. Although the size of the proposed APS is slightly larger than a conventional APS, the dynamic range of the proposed pixel is much wider than a conventional APS. And the proposed APS has a varied dynamic range from adjusting the reference voltage. The proposed APS has been designed and fabricated by using 0.35 mu m 2-poly 4-metal standard CMOS technology, and its characteristics have been evaluated.