A power-optimized widely-tunable 5-GHz monolithic VCO in a digital SOI CMOS technology on high resistivity substrate

TLDR

This paper designs power‑efficient monolithic VCOs with a wide tuning range. Four 5‑GHz LC‑tank VCOs were fabricated in a 0.12‑µm SOI CMOS process on high‑resistivity substrate using single‑ and multi‑layer copper inductors, and a new figure‑of‑merit (FOMT) combining power, phase noise, and tuning range was introduced. The best VCO achieved an FOMT of –189 dBc/Hz, a 22 % tuning range, –126 dBc/Hz phase noise at 1 MHz offset for 4.5 GHz, and oscillated at 5.4 GHz with only 500 µW power.

Abstract

This paper describes the design and technology optimization of power-efficient monolithic VCOs with wide tuning range. Four 5-GHz LC-tank VCOs were fabricated in a 0.12-μm SOI CMOS technology that was not enhanced for RF applications. High and regular resistivity substrates were used, as were single-layer and multiple-layer copper inductors. Using a new figure-of-merit (FOMT) that encompasses power dissipation, phase noise and tuning range, our best VCO has an FOMT of -189 dBc/Hz. The measured frequency tuning range is 22 % and the phase noise is -126 dBc/Hz at 1 MHz offset for 4.5-GHz. Oscillation was achieved at 5.4-GHz at a minimum power consumption of 500 μW.