A 0.5V 10GHz 8-phase LC-VCO Combining current-reuse and back-gate-coupling techniques consuming 2mW

This paper describes an ultra-low-voltage low-power 8-phase voltage-controlled oscillator (VCO) for 10GHz beam-forming satellite receivers. It is composed by four 0.5V current-reuse LC-VCO cells inter-locked by direct-back-gate coupling, featuring independent sizing of coupling strength and frequency tuning, while avoiding the risk of forward bias the substrate p-n junctions. Optimized in 65nm CMOS, the 8-phase VCO draws only 2mW. The phase noise at 1MHz offset is -114dBc/Hz to -110dBc/Hz over a 32.5% tuning range from 8.55 to 11.88GHz. These results correspond to a high-and-stable FOM within -188 to -189.5dBc/Hz.