A dual‐resonance CMOS voltage‐controlled oscillator with enhanced performance through new varactor topology

Abstract

A new fully integrated, dual‐band CMOS voltage controlled oscillator (VCO) is presented. The VCO is composed of a p‐core cross‐coupled and an n‐core cross‐coupled Colpitts oscillator with dual‐resonance LC tank and was implemented in 90‐nm CMOS technology with 1.15 V supply voltage. The circuit allows the VCO to operate at two resonant frequencies with a common LC tank. This VCO is configured with 6.3 and 10 GHz frequency bands with differential outputs. The dual‐band VCO operates at 6.11–6.413 GHz and 9.72–10.24 GHz. The phase noises of the VCO operating at 9.72 and 6.4 GHz are −116.31 dBc/Hz and −122.79 dBc/Hz at 1‐MHz offset, respectively, while the VCO draws 4/4.28 mA and 4.6/4.92 mW consumption at high/low frequency band from a 1.15‐V supply. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1590–1593, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26882

Dual‐band VCO with composite right‐/left‐handed resonator

“…This approach has no switch loss because it uses no MOSFET switch. The dual‐resonance VCO [4, 5] uses a unit of a composite right‐/left‐handed (CRLH) [6] resonator and has drawback of lower low‐band output power than high‐band output power.…”