A 16b 80MS/s 100mW 77.6dB SNR CMOS pipeline ADC

The high channel count of many modern communication systems increasingly requires high-performance ADCs that consume very little power. The 16b pipeline ADC described here achieves 77.6dBFS SNR, 77.6dBFS SNDR and 95dBc SFDR at 80MS/S with a 10MHz input. With a 200MHz input, the ADC achieves 71.0dBFS SNR, 69.4dBFS SNDR and 81dBc SFDR. The complete ADC including reference, clock, and digital circuitry consumes 100mW from a 1.8V supply. This compares favorably with recently reported ADCs in this perform ance class [1-3]. In this paper, several architectural and circuit techniques used to achieve this performance are presented. The techniques include a dynamical ly driven deep N-well input sampling switch, an offset-cancelled comparator, and a back-gate voltage-biased MDAC amplifier. The ADC is fabricated in a 1P5M 0.18μm CMOS process with deep N-well (DNW) isolation.