A highly-tunable 12 GHz quadrature LC-VCO in SiGe BiCMOS process

This paper describes a 12 GHz fully-integrated, fully-differential quadrature LC VCO. Fabricated in a 0.35 /spl mu/m SiGe BiCMOS process with 55 GHz f/sub T/, the oscillator achieves 37% tuning range (9.62 to 14.0 GHz) and exhibits 113.5 and -112.3 dBc/Hz phase noise at 10 MHz away from 11 and 13 GHz oscillation frequencies, respectively. The oscillator draws 39 mA current from a 3.3 V supply and occupies 0.36 mm/sup 2/ active die area.