A low phase noise monolithic VCO in SiGe BiCMOS

A fully integrated, low phase noise, dual-band voltage controlled oscillator (VCO) utilizing a novel tuning scheme is reported. Coarse digital tuning is achieved using MOSFETs and fine analog tuning utilizes PN varactors. The measured phase noise is -95 dBc/Hz max at 3 GHz+25 kHz over the whole tuning bandwidth (/spl plusmn/12.5%), and the power dissipated is 22.5 mW. To our knowledge, these are the best results published so far.