Title :
Low-Voltage, Low-Power, and Wide-Tuning-Range Ring-VCO for Frequency ΔΣ Modulator
Author :
Cao, Tuan-Vu ; Wisland, Dag T. ; Lande, Tor Sverre ; Moradi, Farshad
Author_Institution :
Nanoelectron. group, Univ. of Oslo, Oslo, Norway
Abstract :
A low-voltage, low-power, and wide-tuning-range VCO which converts an analog input voltage to phase information for a frequency ΔΣ modulator is proposed in this paper. The VCO is based on a differential ring oscillator, which is improved with modified symmetric load and a positive feedback in the differential delay cells, a new bias circuit and a full-swing amplifier. The proposed VCO operating with two stages at a power supply voltage of 0.6 V can achieve wide tuning-range and low power consumption of 176.892 uW. The new VCO has a good linearity reducing harmonic distortion for frequency ΔΣ modulator. The circuit is designed using a 65 nm CMOS process.
Keywords :
CMOS integrated circuits; circuit feedback; delta-sigma modulation; frequency modulation; low-power electronics; voltage-controlled oscillators; CMOS process; bias circuit; differential delay cell; differential ring oscillator; frequency ΔΣ modulator; full-swing amplifier; linear harmonic distortion reduction; low-voltage low-power wide-tuning-range ring-VCO; positive feedback; size 65 nm; voltage 0.6 V; Chirp modulation; Delay; Differential amplifiers; Feedback circuits; Frequency conversion; Frequency modulation; Phase modulation; Ring oscillators; Voltage; Voltage-controlled oscillators;
Conference_Titel :
NORCHIP, 2008.
Conference_Location :
Tallinn
Print_ISBN :
978-1-4244-2492-4
Electronic_ISBN :
978-1-4244-2493-1
DOI :
10.1109/NORCHP.2008.4738287
