A Distributed Dual-Band LC Oscillator Based on Mode Switching

In this paper, we present a distributed dual-band LC oscillator suitable for low-phase-noise applications. It switches between the odd and even resonant modes of a fourth-order LC resonator. In contrast to other switched-resonator designs, the switches used for mode selection do not carry current, and therefore, do not affect the quality factor of the resonator, which leads to low phase noise. Analysis shows it achieves the same phase-noise figure-of-merit (FoM) as a single-band LC oscillator that uses the same inductor and active core. This was verified by a prototype in a 0.13-μm CMOS process. It draws a current of 4 mA from a 0.5-V power supply and achieves a FoM of 194.5 dB at the 4.9-GHz band and 193.0 dB at the 6.6-GHz band, which is the same as the reference standalone LC oscillator. There is good agreement among theory, simulation, and measurement results.

[1]  Zhenbiao Li,et al.  A low-phase-noise and low-power multiband CMOS voltage-controlled oscillator , 2005, IEEE Journal of Solid-State Circuits.

[2]  F. Svelto,et al.  A Magnetically Tuned Quadrature Oscillator , 2007, IEEE Journal of Solid-State Circuits.

[3]  A. Demir,et al.  Phase noise in oscillators: a unifying theory and numerical methods for characterization , 2000 .

[4]  P. Andreani,et al.  On the phase-noise and phase-error performances of multiphase LC CMOS VCOs , 2004, IEEE Journal of Solid-State Circuits.

[5]  K. O. Kenneth,et al.  Demonstration of a switched resonator concept in a dual-band monolithic CMOS LC-tuned VCO , 2001, Proceedings of the IEEE 2001 Custom Integrated Circuits Conference (Cat. No.01CH37169).

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

[7]  A.L. Lacaita,et al.  5-GHz Oscillator Array With Reduced Flicker Up-Conversion in 0.13-$muhboxm$CMOS , 2006, IEEE Journal of Solid-State Circuits.

[8]  P. Wambacq,et al.  A Compact Wideband Front-End Using a Single-Inductor Dual-Band VCO in 90 nm Digital CMOS , 2008, IEEE Journal of Solid-State Circuits.

[9]  Svetozar S. Broussev,et al.  Dual-Band LC VCO Architecture With a Fourth-Order Resonator , 2007, IEEE Transactions on Circuits and Systems II: Express Briefs.

[10]  Almudena Suarez,et al.  Analytical comparison between time- and frequency-domain techniques for phase-noise analysis , 2002 .

[11]  A. Abidi,et al.  Physical processes of phase noise in differential LC oscillators , 2000, Proceedings of the IEEE 2000 Custom Integrated Circuits Conference (Cat. No.00CH37044).

[12]  Pietro Andreani,et al.  More on the Phase Noise Performance of CMOS , 2006 .

[13]  K. Kurokawa,et al.  Noise in Synchronized Oscillators , 1968 .

[14]  A. Mazzanti,et al.  Class-C Harmonic CMOS VCOs, With a General Result on Phase Noise , 2008, IEEE Journal of Solid-State Circuits.

[15]  Eun-Chul Park,et al.  Wideband VCO With Simultaneous Switching of Frequency Band, Active Core, and Varactor Size , 2007, IEEE Journal of Solid-State Circuits.

[16]  P. Gregorius,et al.  A compact triple-band low-jitter digital LC PLL with programmable coil in 130-nm CMOS , 2005, IEEE Journal of Solid-State Circuits.

[17]  Asad A. Abidi,et al.  RF-CMOS oscillators with switched tuning , 1998, Proceedings of the IEEE 1998 Custom Integrated Circuits Conference (Cat. No.98CH36143).

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

[19]  Tatsuo Itoh,et al.  A dual band mm-wave CMOS oscillator with left-handed resonator , 2009, 2009 IEEE Radio Frequency Integrated Circuits Symposium.

[20]  Xudong Cao,et al.  Phase noise in coupled oscillators: theory and experiment , 1997 .

[21]  Mona Mostafa Hella,et al.  A 1.94 to 2.55 GHz, 3.6 to 4.77 GHz Tunable CMOS VCO Based on Double-Tuned, Double-Driven Coupled Resonators , 2009, IEEE Journal of Solid-State Circuits.

[22]  H. Jacobsson,et al.  Very low phase-noise fully-integrated coupled VCOs , 2002, 2002 IEEE Radio Frequency Integrated Circuits (RFIC) Symposium. Digest of Papers (Cat. No.02CH37280).

[23]  A. Goel,et al.  Frequency Switching in Dual-Resonance Oscillators , 2007, IEEE Journal of Solid-State Circuits.

[24]  A. Fard,et al.  More on the $1/{\rm f}^{2}$ Phase Noise Performance of CMOS Differential-Pair LC-Tank Oscillators , 2006, IEEE Journal of Solid-State Circuits.

[25]  Hossein Hashemi,et al.  Wideband Multi-Mode CMOS VCO Design Using Coupled Inductors , 2009, IEEE Transactions on Circuits and Systems I: Regular Papers.