A low phase noise Colpitts VCO for Ku-band applications

A 12.74 GHz low phase noise Colpitts VCO has been designed and fabricated in a 0.25μm SiGe:C BiCMOS technology. The balanced VCO uses a transformer coupled tank and two additional inductors to reduce the current in the feedback loop. The efficiency of energy transfer from active devices to the tank has been improved by these two methods, which leads to a larger output swing for the same DC current. Measured phase noise is better than -100dBc /Hz at 100 kHz offset over the tuning range from 12.43 to 13.08GHz.

[1]  Hwann-Kaeo Chiou,et al.  Low phase noise Ku-band Gm-boosting differential Colpitts VCO , 2009, 2009 Asia Pacific Microwave Conference.

[2]  Ali M. Niknejad,et al.  A 4-port-inductor-based VCO coupling method for phase noise reduction , 2011, IEEE Custom Integrated Circuits Conference 2010.

[3]  Kun-You Lin,et al.  A K-band CMOS low power modified colpitts VCO using transformer feedback , 2009, 2009 IEEE MTT-S International Microwave Symposium Digest.

[4]  Ali Hajimiri,et al.  Concepts and methods in optimization of integrated LC VCOs , 2001, IEEE J. Solid State Circuits.

[5]  Robert Weigel,et al.  A low phase-noise SiGe Colpitts VCO with wide tuning range for UWB applications , 2010, The 5th European Microwave Integrated Circuits Conference.

[6]  J. Melai,et al.  BiCMOS technology improvements for microwave application , 2008, 2008 IEEE Bipolar/BiCMOS Circuits and Technology Meeting.

[7]  Xueyang Geng,et al.  An 8.7–13.8 GHz transformer-coupled varactor-less quadrature current-controlled oscillator RFIC , 2009, 2009 IEEE Bipolar/BiCMOS Circuits and Technology Meeting.

[8]  E. van der Heijden,et al.  Colpitts VCOs for low-phase noise and low-power applications with transformer-coupled tank , 2008, 2008 IEEE Radio Frequency Integrated Circuits Symposium.

[9]  T. Biondi,et al.  A 18-GHz silicon bipolar VCO with transformer-based resonator , 2006, IEEE Radio Frequency Integrated Circuits (RFIC) Symposium, 2006.

[10]  A. Fard,et al.  A study of phase noise in colpitts and LC-tank CMOS oscillators , 2005, IEEE Journal of Solid-State Circuits.