Design of a 2.4 GHz Low Phase Noise CMOS LC VCO for Wireless Applications

Abstract: This paper presents the design of a 2.4 GHz CMOS LC voltage controlled oscillator (VCO) in TSMC 130 nm CMOS process. In this paper three different topologies of LC-tank VCO design for low phase noise and low power consumption are studied. Comparison is made between the VCO topologies considering their effect on the parameters such as phase noise, power dissipation, tuning range, tuning sensitivity. The effects of these parameters on the VCO performance are discussed. The proposed design is simulated using ADS Tool and operates from a supply voltage of 1.8 V. After simulating the proposed design the VCO shows a phase noise of -128.68 dBc/Hz at 1 MHz offset frequency from a 2.4 GHz carrier signal. The frequency of the VCO ranges from 2.36 GHz to 2.61 GHz when the control voltage is varried from 0 to 2 V. The FOM is obtained as -183.73 dBc/Hz.

Keywords: VCO, CMOS process, NMOS cross-coupled, LC tank, Phase noise, ADS (Advanced Design System), Figure of Merit.