AN IMPROVED CORRELATED DOUBLE SAMPLING CIRCUIT FOR LOW-NOISE CHARGE-COUPLED-DEVICES

Correlated double sampling (CDS) is a widespread noise reduction method for the discrete-time output signals of charge-coupled devices (CCD). This paper describes an improved CDS circuit with noise performance superior to the classical one, at the hardware expense of only one additional FET switch. By allowing a smaller noise band-width, the total noise contribution from the video amplifier can be reduced, and pixel crosstalk and kTC noise will even be completely eliminated. It is shown that the proposed approach is close to optimum filtering. © 1990 IEEE