An optimized 2.4 GHz CMOS LC-tank VCO with 0.55 %/V frequency pushing and 516 MHz tuning range

A low frequency pushing wide frequency tuning range radio frequency (RF) voltage-controlled oscillator (VCO) in 0.35 /spl mu/m standard CMOS process for wireless applications is presented. It is different from all conventional designs primarily in the way it is biased. The measurement results show that the proposed structure reduces the frequency pushing to 0.55%/V and increases the frequency tuning range to 516 MHz. It provides a minimum figure of merit for oscillators (FOM) of about -180 dBc/Hz following the optimization method. The main contributions include: (a) the proposed VCO structure, (b) the FOM optimization method and (c) the silicon results.