CMOS IMAGE SENSORS - ELECTRONIC CAMERA-ON-A-CHIP

CMOS active pixel sensors (APS) have performance competitive with char ge-coupled device (CCD) technology, and offer advantages in on-chip fu nctionality, system power reduction, cost, and miniaturization. This p aper discusses the requirements for CMOS image sensors and their histo rical development. CMOS devices and circuits for pixels, analog signal chain, and on-chip analog-to-digital conversion are reviewed and disc ussed.