USN용 12비트 연속 근사화 아날로그-디지털 변환기 설계

Abstract

The recent advance in ubiquitous technology has grown many changes in human life. Variety of informations that exist in nature are provided to people with the USN(Ubiquitous Sensor Network). The information includes analog signal of various types, and there are many difficulties to process the various analog informations. To solve these problems, ADC(Analog-to-Digital Converter) is required in USN. This thesis presents the design of SAR(Successive Approximation Register) ADC for USN. The proposed SAR ADC consists of sample-and-hold stage, capacitor array network stage, SAR control logic stage, comparator stage, DAC stage and DAC control logic stage. This SAR ADC is designed to have performance of 12-bit resolution and 1MSps(1 Mega Sampling per second). The proposed circuit is designed using Magnachip/SK Hynix 0.18μm CMOS 1Poly-6Metal process, and it is powered by 1.8V supply. To reduce chip area and power dissipation, we minimized unit capacitor area and number of the total capacitors, and designed the circuit considering optimization as compared to conventional circuits. The proposed circuit in this thesis showed high SNDR(Signal-to-Noise Distortion Ratio) of 70.03dB, and excellent effective bit number of 11.34-bit as compared to conventional research results. The designed circuit also showed low power dissipation of 3.24mW, and small chip area of 0.56mm². The proposed ADC is applicable for the signal conversion of the industry system application.