A high-speed CMOS image sensor for real-time vision chip

A high-speed CMOS image sensor for real-time vision chip is proposed. The high-speed CMOS image sensor consists of CMOS photodiode array, correlated double sampling(CDS) array, programmable gain amplifier(PGA) array, area-efficient single-slope analog-to-digital converter(ADC) array and controller circuit. It can perform the image capturing and row-parallel signal processing. It outputs digital signal or digital image at a frame rate of over1000 frame/s. It can reduce the fixed pattern noise(FPN) and amplify(or shrink) the output signals of the photodiode array to maintain the amplitude of the signal in row-parallel fashion. It can continuously perform8-bit ADC conversion in row-parallel. A128 pixel×128 pixel image sensor with128 rows of CDS, PGA and single-slope ADC is fabricated by using0.18μm1P6M CMOS process. The chip size is2.2 mm×2.6 mm. The measured results demonstrate that the designed chip can perform high-speed real-time optical signal capturing and processing. It can be applied to the real-time vision chip system.