Performance Comparison of 2.5-GHz LC Voltage-Controlled Oscillator for Three Different Technology Nodes

Abstract

This paper has been written to compare the performances of LC Voltage Controlled Oscillator (VCO) at 2.5 GHz to see the effects of device performances with different technology node on the same while keeping the circuits identical. Accordingly, as a case study, three instances of LC-VCO have been designed in Cadence Spectre using GPDK 45nm, 90nm, and 180nm technology and three different power supply levels of 0.8 V, 1 V, and 1.2 V respectively. ObservedPhase Noise (PN) for 45nm, 90nm, and 180nm technology are −120.8 dBc/Hz, −124.64 dBc/Hz and −126.12 dBc/Hz @ 1MHz offset respectively. Output power, Figure of Merit (FOM) and $\mathbf{K}_{\mathbf{VCO}}$ also have been measured subsequently. The best possible FOM obtained are −181.7dB, −184.9dB and −186.2dB for 45nm, 90nm and 180nm technology node respectively.