Immediate Calibration of Operational Ampli fier Gain Error in Pipelined ADCs Usin

Abstract

This paper introduces extended correlated double sampling (ECDS) as a new gain-calibration technique in pipelined analog-to-digital converters (ADCs). The proposed calibration simultaneously improves the effective dc gain and increases the maximum output swing of the opamps with given overdrive volt- ages. Furthermore, ECDS is immediate, thus avoiding the long convergence time associated wit h many background calibration schemes. This characteristic make s it desirable for applications where the