A 10-bit 10-MS/s SAR ADC with a Reference Driver

Abstract

This paper presents a 10 bit successive approximation register (SAR) analog-to-digital converter (ADC) with a reference driver. The proposed SAR ADC consists of a capacitive digital-to-analog converter (CDAC), a comparator, a SAR logic, and a reference driver which improves the immunity to the power supply noise. The reference driver generates the reference voltages of 0.45 V and 1.35 V for the SAR ADC with an input voltage range of ±0.9 V. The SAR ADC is implemented using a 0.18-μm CMOS technology with a 1.8-V supply. The proposed SAR ADC including the reference driver almost maintains an input voltage range to be ±0.9 V although the variation of supply voltage is +/-200 mV. It consumes 5.32 mW at a sampling rate of 10 MS/s. The measured ENOB, DNL, and INL of the ADC are 9.11 bit, +0.60/-0.74 LSB, and +0.69/-0.65 LSB, respectively.