A 70dB 40MHz Pipelined-SAR With Digital CLS

This paper presents digital correlated level shifting, a new correlated level shifting technique that leverages the digital output codes of the quantizers in a pipelined ADC to suppress errors associated with residue amplifier gain and linearity. The prototype 13-bit 40 MHz Pipelined-SAR ADC demonstrates a 22 dB improvement in SFDR and 13dB improvement in SNDR when the technique is enabled, and close to $4 x$ improvement in performance versus power.