Active inductor based low phase noise voltage controlled oscillator

Abstract

This paper proposed a fully MOS-based voltage-controlled oscillator (VCO) with tuning range and low phase noise, replacing the most often used NMOS-based inductor-capacitor tank arranged in cross-coupled topology with a high-Q active inductor. This study mainly focuses on VCO design using a MOS-based active inductor and is implemented and verified using UMC 180nm CMOS technology. The proposed VCO is resistorless and consists of an active inductor, two MOS capacitors, and the buffer circuits. The fundamental principle of this MOS-based VCO concept is to use MOS based inductor to replace the passive inductor, which is an active inductor that gives less area and low power usage. At 1 MHz frequency offset, the phase noise achieved by this proposed configuration is -102.78dBc/Hz. In the proposed VCO architecture, the frequency tuning range is 0.5GHz to 1.7GHz. This VCO design can accomplish this acceptable tuning range by altering the regulating voltage from 0.7V to 1.8V. This suggested architecture of proposed VCO design has the power consumption of 9mW with a 1.8V supply voltage. The suggested VCO has been shown to be a good fit for low-power RF circuit applications while preserving acceptable performance metrics.