An Ultra-Low-Power 65 nm Single-Tank 24.5-to-29.1 GHz Gm-Enhanced CMOS LC VCO Achieving 195.2 dBc/Hz FoM at 1 MHz

Abstract

A low-power single-core 24.5-to-29.1 GHz CMOS LC voltage-controlled oscillator (VCO) is presented. The proposed VCO uses an innovative differential cross-coupled architecture in which an additional pair is connected to the main pair to increase the effective transconductance, resulting in lower power consumption and reduced phase noise (PN). The proposed VCO is fabricated in a 1P9M standard CMOS process and sustains oscillation at 29.14 GHz with power consumption as low as 455 μW (650 μA from a 0.7 V supply), which is ~20% lower than a conventional CMOS LC VCO without Gm-enhanced differential pairs built through the same process (700 μA from 0.8 V supply). When consuming 880 μW (1.1 mA from 0.8 V), the proposed VCO exhibits a tuning range of 4.6 GHz (from 24.5 GHz to 29.1 GHz). Moreover, it exhibits a measured phase noise (PN) better than −106.5 dBc/Hz @ 1 MHz and −132.0 dBc/Hz @ 10 MHz, with figure-of-merit (FoM) results of 195.2 dBc/Hz and 200.3 dBc/Hz, respectively.