Method and system for asynchronous successive approximation register (sar) analog-to-digital converters (adcs)

Abstract

Methods and systems are provided for asynchronous successive approximation register (SAR) analog-to-digital converters (ADCs) that utilize preemptive bit setting decisions. In particular, such SAR ADC may be operable to, when a failure to determine a valid output decision for each comparison step occurs, set one or more remaining bits, up to but not including one or more overlapping redundant bits in a code word corresponding to the comparison step, to a particular value. The value may be derived from a value of a bit determined in an immediately preceding decision. The failure may be determined based on dynamic and/or adaptive criteria. The criteria may be set, e.g., so as to guarantee that a magnitude of a difference between an analog input voltage to the SAR ADC and analog output voltage of a digital-to-analog converter (DAC) used therein is within overlapping ranges of voltages corresponding to the overlapping redundant bits.