A 3-band switched-inductor LC VCO and differential current re-use doubler achieving 0.7-to-11.6 GHz tuning range

Abstract

This paper presents a 3-bit switched inductor, 8-bit switched capacitor VCO utilizing frequency aware switch sizing to achieve 157% tuning range (0.7-5.8 GHz). Implemented in 65nm CMOS, the VCO maintains phase noise between -128 and -116 dBc/Hz at 1MHz offset across the tuning range. A current reuse differential frequency doubler extends the tuning range to 0.7-11.6 GHz (177%). The FOMTs of the stand alone VCO as well as that of the VCO-doubler combination vary between 191 to 209 dBc/Hz over their respective tuning ranges.