A global shutter CMOS image sensor with wide dynamic range pixel

Abstract

A novel five transistor global shutter CMOS active pixel with ultra-high dynamic range is presented in this paper. A global shutter control transistor is added to traditional four transistor pixel. The five transistor pixel image sensor works in global shutter mode to shoot high speed moving object with dual sampling to eliminate fixed pattern noise. The image sensor can restore four transistor pixel rolling shutter mode with global shutter control transistor shutoff to shoot stationary object with correlated dual sampling to eliminate fixed pattern noise and random noise. A digital control stepped reset-gate voltage technique with no additional components to increase dynamic range by the compression of charge integration characteristic curve and to implement anti-blooming by discharging excess carriers is adopted. Simulation results show that the image sensor can work in global shutter mode and the dynamic range is increased approximately by 20dB than typical CMOS image sensor.