A 21-to-54.5GHz transformer-coupled varactorless 45nm CMOS VCO

A dual-resonance mode millimeter-wave VCO with a transformer-coupled resonator in 45nm SOI CMOS is presented that achieves a record tuning range of 88.5% and generates frequencies in 21.1-to-54.5GHz range while consuming only 8-16mW from a 1V supply. Switched capacitor banks and a switched coupled inductor provide coarse tuning, while fine frequency tuning is performed with current-mode tuning. With phase noise lower than -107dBc/Hz at 10MHz offset, the FOM_T of this VCO is better than-185.4 dB.