A low phase noise wideband VCO in 65nm RF CMOS for low power applications

A wideband LC VCO used in low power and phase noise applications is described. A phase noise model is utilized for its lower phase noise design. A switched capacitor array, two power supply and substrate noise filters are involved in the circuit. The phase noise imported by the MOS channel current and tank less resistance is modeled to give approximate evaluation of the circuit performance. The circuit has been implemented in a standard 65 nm CMOS technology. The test result indicates that the frequency of the VCO is from 750 MHz to 1.5 GHz, and the phase noise is -125.84 dBc/Hz @1 MHz in 1.21GHz. The chip consumes less than 2.25 mW with 1.2 V power supply, and occupies 0.7 mm2 areas.

[1]  G. Szczepkowski,et al.  Wideband 0.18μm CMOS VCO using active inductor with negative resistance , 2007, 2007 18th European Conference on Circuit Theory and Design.

[2]  Bodhisatwa Sadhu,et al.  Capacitor bank design for wide tuning range LC VCOs: 850MHz-7.1GHz (157%) , 2010, Proceedings of 2010 IEEE International Symposium on Circuits and Systems.

[3]  T.H. Lee,et al.  Oscillator phase noise: a tutorial , 1999, IEEE Journal of Solid-State Circuits.

[4]  A.M. Niknejad,et al.  A 1.8-GHz LC VCO with 1.3-GHz tuning range and digital amplitude calibration , 2005, IEEE Journal of Solid-State Circuits.

[5]  Liang-Hung Lu,et al.  A Wide Tuning-Range CMOS VCO With a Differential Tunable Active Inductor , 2006, IEEE Transactions on Microwave Theory and Techniques.

[6]  N. Itoh,et al.  A 92.6 % tuning range VCO utilizing simultaneously controlling of transformers and MOS varactors in 0.13 µm CMOS technology , 2009, 2009 IEEE Radio Frequency Integrated Circuits Symposium.

[7]  T.H. Lee,et al.  Phase noise in CMOS differential LC oscillators , 1998, 1998 Symposium on VLSI Circuits. Digest of Technical Papers (Cat. No.98CH36215).

[8]  Jaewook Shin,et al.  A Wide-Band CMOS LC VCO With Linearized Coarse Tuning Characteristics , 2008, IEEE Transactions on Circuits and Systems II: Express Briefs.

[9]  A. Hajimiri,et al.  Design issues in CMOS differential LC oscillators , 1999, IEEE J. Solid State Circuits.

[10]  Ali Hajimiri,et al.  A general theory of phase noise in electrical oscillators , 1998 .

[11]  Zhigong Wang,et al.  Wideband CMOS LC VCO Design and Phase Noise Analysis , 2008 .