A 0.027-mm² Self-Calibrating Successive Approximation ADC Core in 0.18-µm CMOS

Abstract

We present a 10-bit 1-MS/s successive approximation analog-to-digital converter core including a charge redistribution digital-to-analog converter and a comparator. A new linearity calibration technique enables use of a nearly minimum capacitor limited by kT/C noise. The ADC core without digital control blocks has been fabricated in a 0.18-µm CMOS process and consumes 118µW at 1.8V power supply. Also, the active area of ADC core is realized to be 0.027mm². The calibration improves the SNDR by 13.4dB and the SFDR by 21.0dB. The measured SNDR and SFDR at 1kHz input are 55.2dB and 73.2dB respectively.