Design of a 45nm 8-bit 2GS/s 250mW CMOS Folding A/D Converter with an Adaptive Digital Error Correction Technique

Abstract

An 8-bit 2GS/s 250mW low power folding A/D converter(ADC) with a 45nm CMOS technology is described. In order to reduce the power consumption, a new folding block with a shut-down circuit is proposed. The role of shut-down circuit selectively cuts off the power supply of folding amplifiers, according to the input analog voltage. Further, an adaptive digital error correction technique is discussed to reduce the code errors. The proposed ADC has been fabricated with a 1.2V 45nm 1-poly 8-metal CMOS process. The effective chip area is 1.98mm(2) (ADC core : 1.1mm(2), Calibration : 0.88mm(2)) and the power consumption is about 250mW. The measured SNDR is 46dB at the conversion rate of 2GS/s. The measured values of INL and DNL are within 2.5LSB and 1.0 LSB, respectively.