A nonuniform quantization scheme for high speed SAR ADC architecture

Abstract

We introduce a new signal sampling scheme which allows high quality signal conversion to overcome the constraint of effective number of bits in high speed signal acquisition. The proposed scheme is based on the popular successive approximation register (SAR) and employs compressive sensing technique to increase the resolution of a SAR analog-to-digital converter (ADC) architecture. We present signal acquisition and recovery model which provides better performance in signal acquisition. The sampled signal shows higher resolution after recovery than conventional compressive sensing based sampling schemes. Circuit level architecture is discussed to implement the proposed scheme using the SAR ADC architecture. Simulation result shows that the proposed nonuniform quantization strategy can be a way to overcome the sampling rate-resolution limitation which is a challenging problem in SAR ADC design even with the most advanced technology.