PVT tolerant LC-VCO in 90 nm CMOS technology for GPS/Galileo applications

Abstract

In this paper low-voltage LC voltage-controlled oscillator (VCO) with low sensitivity to process, voltage and temperature (PVT) variations has been presented. VCO operates at 3.2 GHz and its output signal frequency is divided by 2 in quadrature divider to generate quadrature signals at 1.6 GHz. The NMOS cross-coupled architecture, proper varactor biasing, tuning curve linearization technique and switched-capacitor (SC) current source were used to reduce the sensitivity to PVT variations. The LC-VCO was designed with the usage of Low-Leakage UMC 90 nm CMOS technology. It achieves phase noise of −117 dBc/Hz at 1 MHz offset and draws 1.2 mA (VCO+Quadrature Divider) from 1.2 V supply voltage.