Title :
A VCO based continuous time delta sigma ADC with 10MHz BW 55dB SNR and 42dB SNDR
Author :
Zhang, X.L. ; Chen, J.Z. ; Xu, Z.T. ; Yu, Qian ; Liu, Yanbing
Author_Institution :
State Key Lab. of Electron. Thin Films & Integrated Devices, Univ. of Electron. Sci. & Technol. of China, Chengdu, China
Abstract :
This paper explores a continuous time (CT) delta sigma (ΣΔ) ADC with a VCO based quantizer. The prototype is designed in 0.18 um RF CMOS with a post simulated performance of 55/42 dB SNR/SNDR over a 10MHz bandwidth, while consuming 9.8mA from a 1.8 V supply and occupying a die area of 0.4mm2 without bonding pad. The key element of the ADC, namely a 4 bit VCO based quantizer, converts voltage signal to frequency signal and quantizes the corresponding frequency to thermometer code at 400 MS/s.
Keywords :
analogue-digital conversion; continuous time systems; delta-sigma modulation; voltage-controlled oscillators; CT ΣΔ ADC; VCO; continuous time delta sigma ADC; frequency 10 MHz; Bandwidth; Clocks; Delays; Passive filters; Sigma-delta modulation; Topology; Voltage-controlled oscillators; CT delta sigma; Ring oscillator; VCO-based quantize;
Conference_Titel :
Electron Devices and Solid State Circuit (EDSSC), 2012 IEEE International Conference on
Conference_Location :
Bangkok
Print_ISBN :
978-1-4673-5694-7
DOI :
10.1109/EDSSC.2012.6482893
