Design of 20 GHz high performance LC-VCOs in a 52 GHz fT SiGe:C BiCMOS technology

The design and analysis of fully integrated 20 GHz voltage controlled oscillators (VCOs) for low cost and low power communication system are presented in this paper. Two differential topographies have been studied: balanced Colpitts VCO and LC-VCO using a cross-coupled differential pair. We have focused on oscillation frequency, tuning range, phase noise, output power optimization and buffer stage specifications. SiGe:C hetero-junction bipolar transistors of a 52 GHz cut-off frequency have been used and produced via a monolithic BiCMOS technology.