This paper presents a novel architecture of a SAR assisted 2 step ADC where the SAR residue is quantized with a bidirectional digital slope time-based converter. The bidirectional slope halves the conversion time of the second stage. Furthermore, the redundancy requirements in the second stage are considerably reduced through a unified global calibration scheme. A practical example is given for a 12-bit 64 MS/s ADC with 67 dB SNDR and 208 µW estimated power consumption targeted at ultra-low power RF receivers. The complete architecture including calibration has been validated with VerilogA models including capacitor mismatch, comparator offsets and noise.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.