A dual core wideband CMOS LC VCO with low tuning sensitivity

Abstract

A dual core wideband CMOS LC VCO has been designed and fabricated in TSMC 0.25μm RF CMOS 1P5M process. Using a combination of a switched capacitor array and a switched varactor array, this VCO achieves a frequency tuning rang of 800MHz to 1730MHz with a control voltage varying from 0.2V-2.2V, while maintaining a tuning sensitivity of less than 50MHz/V.The measured single-side phase noise is -120dBc/Hz at a 1MHz offset from a 1060MHz carrier when the VCO core is drawing 8mA from a 2.5V supply.