A 10b Ternary SAR ADC with decision time quantization based redundancy

Abstract

The design of a Ternary Successive Approximation ADC (TSAR) with decision time quantization is proposed. The TSAR examines the transient information of the typical SAR comparator to provide full half-bit redundancy, an increased monotonicity switching algorithm, speed enhancements without inherent metastability, residue shaping effects, and stage skipping. A prototype is fabricated in 0.13μm CMOS employing on-chip statistical time reference calibration and supply variability from 0.8 to 1.2V. The chip consumes 84μW at 8 MHz for a FOM of 16fJ/C-S.