Title
A dual-band CMOS LC-VCO with highly linear frequency tuning characteristics
Abstract
A dual-band wide range LC voltage controlled oscillator (VCO) with highly linear frequency tuning characteristics for GNSS application is presented. The linearity of VCO includes the coarse and fine tuning sensitivity variations, which are defined as the frequency step per-code (fstep) variation and the VCO gain (KVCO) variation, respectively. Compared to the conventional circuit topology, the proposed VCO utilizes the 4-bit (Bit) digital signal to control a varactors array instead of the switched capacitors bank to realize the linear coarse tuning. And the 4-bit digital signal also controls the other varactors array to reduce the variation of the VCO gain. Measurement results illustrate that the output frequency range covers the whole GNSS bands with fstep and KVCO almost keeping constant. Thanks to the good linearity, the designed VCO obtains a low phase noise of -124dBc/Hz at 1MHz offset from 3.018GHz output frequency while consuming only 5mA from 1.8V supply. The proposed circuit is fabricated in 0.18µm CMOS process and the die area is 0.7mm×0.7mm.
Year
DOI
Venue
2015
10.1016/j.mejo.2015.06.001
Microelectronics Journal
Keywords
Field
DocType
CMOS LC-VCO,Linearity,Varactors,Wide band,Low phase noise,GNSS
Capacitor,Digital signal,Linearity,Phase noise,Voltage-controlled oscillator,CMOS,Electronic engineering,Engineering,Topology (electrical circuits),Multi-band device
Journal
Volume
Issue
ISSN
46
12
0026-2692
Citations 
PageRank 
References 
3
0.42
5
Authors
5
Name
Order
Citations
PageRank
Yanbin Luo130.42
Chengyan Ma230.42
Yebing Gan330.76
Min Qian430.42
Tianchun Ye5308.32