Fully integrated differential VCO with buffer amplifier using 0.35 3/spl mu/m SiGe BiCMOS for C-Band wireless RE transceiver

Abstract

This paper addresses fully integrated positive tuning differential 4.7 GHz VCO fabricated in 0.35 /spl mu/m SiGe BiCMOS process with f/sub t/ of 45 GHz utilizing ground shield layer structure upon low resistive silicon substrate. VCO circuit consists of a cross-coupled differential pair with a parallel resonator connected between the collector nodes and a pair of emitter-following buffer amplifiers. The VCO achieves -5.17 dBm output power with positive tuning frequency range of 509 MHz by positive voltage tuning of 3 V and exhibits -107 dBc/Hz phase noise at 1 MHz away from 4.64 GHz oscillating frequency. The oscillator draws 18 mA current from a 3V supply and occupies 0.67 mm by 0.97 mm die area.