A novel pixel circuit of high dynamic range CMOS image sensor (CIS) was presented for the applications of visual prosthesis

which used the conditional overflow capacitors and multiple integration technologies to achieve high dynamic range

high sensitivity and high signal to noise ratio (SNR) requirements.The designed circuit was simulated using Chartered Semiconductor 0.35 μm CMOS process model parameters

the simulating results showed that the dynamic range was increased by about 62dB than the traditional 4 Transistor Active Pixel Sensor (4T APS) circuit

and the SNR and sensitivity were as high as the 4T APS in weak signal conditions.