Efficient pipelined ADCs using integer gain MDACs

Power consumption of pipelined ADCs is a strong function of the number of bits resolved per stage, particularly for high-performance ADCs. Despite this, conventional design techniques continue to use interstage gain levels of 2N which leave significant gaps in the design space, limiting the extent of optimization. This paper discusses a design method for arbitrary integer-valued interstage gain which retain all benefits of conventional schemes while optimizing power consumption. To demonstrate the practical benefits, a prototype 16-bit 20 Msps ADC with a target power consumption of 200 mW is designed using the proposed techniques.