A −197.3 dBc/Hz FoMT Wideband LC-VCO IC with an I-MOS Based Novel Varactor in 40-nm SOI CMOS

This paper presents a wideband excellent FoMT LC-VCO IC with a novel varactor controlled by a single tuning voltage. The novel varactor includes an Inversion-MOS (IMOS) and an MIM capacitor to widen the capacitance variation. The proposed wideband VCO IC is designed, fabricated and fully evaluated on wafer in 40-nm SOI CMOS. The proposed VCO IC has a completely continuous frequency tuning range from 4.14 GHz to 6.23 GHz (40.3 %) and a -131.0-dBc/Hz measured phase noise at 10-MHz offset frequency from the oscillation frequency of 4.14 GHz. Moreover, the VCO IC has exhibited a measured FoMT of -197.3 dBc/Hz under a 0.34-V supply voltage.