A low-kickback preamplifier with offset cancellation for pipelined folding A/D Converter

This paper presents an offset cancellation preamplifier applied to a pipelined folding A/D Converter. A simple and effective neutralization technique is implemented to reduce the kickback noise. The offset storage technique is realized with switched capacitor circuits to eliminate the effect on the resolution from input offset voltage. By Monte Carlo analysis, the preamplifier with offset variance of 3.24mV is verified operating in 200MHz sampling frequency. The dissipation power is 362μW at 1.8V with a 35×90 μm² area in 0.18μm CMOS.