Tuning Range Of Voltage-controlled Oscillator Research Articles

A 267 GHz Wide Tuning Range VCO With −3.5 dBm Peak Output Power in 40-nm CMOS

This article presents a highly efficient, wide tuning range push-push voltage-controlled oscillator (VCO) in the sub-terahertz frequency band. The proposed VCO adopted a novel capacitance-splitting feedback technique to achieve high oscillation frequency and output power. The frequency tuning is provided through a tunable source degeneration (TSD) network. The proposed TSD network enables a wide tuning range without substantially sacrificing output power. The proposed VCO is fabricated in a 40-nm complementary metal-oxide-semiconductor (CMOS) process and has a peak output power of −3.5 dBm, a center frequency of 267.2 GHz, and a continuous tuning range of 27 GHz. The VCO consumes 30 mA current from a 1.1 V dc supply, resulting in 1.35% dc-to-RF efficiency.

Differential RVCO with low power, low phase noise and wider tuning range for PLL application

ABSTRACT A differential ring CMOS voltage-controlled oscillator (VCO) with dual-delay path topology is proposed in this paper. In this work, the focus area is to improve the tuning range of VCO and phase noise performance of the VCO. The dual-delay path topology is used with P-MOS as load in series with negative-skewed delay transistors. This design gives the wider tuning range and this increases the phase noise performance of the VCO. After the post-layout simulation, frequency tuning range and power dissipation range are 730 MHz to 2.81 GHz and from 1.32 mW to 4.62 mW respectively. The phase noise for this VCO is −97.35 dBc/Hz at 1 MHz offset. The technology used in this work was taken from the library of SCL 180 nm technology. This design exhibits excellent phase noise performance.

A New Boosted Active-Capacitor With Negative-G m for Wide Tuning Range VCOs

A new boosted active-capacitor (BAC) architecture using LC-tuned active-impedance-conversion is presented. In the chosen frequency range, the proposed BAC acts as a tunable capacitance multiplier and negative-transconductance, but where the positive-transconductance is not multiplied. The BAC is used as a low-loss tunable capacitor bank element for designing a wide tuning range voltage-controlled oscillator (VCO). A current-reuse technique is used to lower power consumption and suppress potential parasitic oscillation modes. A zero-capacitance-variation biasing is proposed for a BAC-VCO robust against process, voltage, and temperature variations. The BAC designed in a 65 nm bulk CMOS process achieves a capacitance tuning ratio of 7.8 with a quality factor of higher than 20 across VCO's tuning range. The BAC-VCO prototype has a tuning range of 8.3-14.3 GHz using less than 5 mW core power and achieves FoMT of up to -202.4 dBc/Hz.

A 19.5-GHz 28-nm Class-C CMOS VCO, With a Reasonably Rigorous Result on 1/f Noise Upconversion Caused by Short-Channel Effects

Class-C operation is leveraged to implement a $K$ -band CMOS voltage-controlled oscillator (VCO) where the upconversion of $1/f$ current noise from the cross-coupled transistors in the oscillator core is robustly contained at a very low level. Implemented in a bulk 28-nm CMOS technology, the 12%-tuning-range VCO shows a phase noise as low as −112 dBc/Hz at 1-MHz offset (−86 dBc/Hz at 100 kHz offset) from a 19.5 GHz carrier while consuming 20.7 mW, achieving a figure of merit (FoM) of −185 dBc/Hz. The design is complemented by a theoretical investigation of $1/f$ noise upconversion caused by short-channel effects in the cross-coupled transistors, obtaining the first instance of a closed-form phase noise expression in the $1/f^{3}$ region.

Plans for Planar: Phase-Noise Reduction Techniques in Voltage-Controlled Oscillators

To ensure spectral purity in modern RF signal sources, microwave oscillators and voltage-controlled oscillators (VCOs) must be designed to perform with low phase noise. Despite the growth of monolithic microwave integrated circuits (MMICs), microstrip planar technology is still used for developing low-phase-noise VCOs due to its design simplicity and low manufacturing cost. This article reviews the attributes of low-phase-noise VCOs and some recent techniques applied for phase-noise reduction in microstrip planar technology. The major challenge in designing VCOs in microstrip planar technology lies in improving the quality factor (Q) of resonators. Different methods to improve Q are presented here for techniques incorporated with microstrip lines and substrate integrated waveguides (SIWs). The tradeoff involved with the tuning range (TR) of VCOs is also emphasized to introduce the design selectivity for wideband applications.

A wide tuning range VCO design using multi-pass loop complementary current control with IMOS varactor for low power applications

In this work a wide-bandwidth low-power voltage-controlled oscillator (VCO) design is presented using a new differential delay cell with complementary current control mechanism and inversion mode MOSFET (IMOS) varactor. The variations in output oscillation frequency of the VCO has been achieved by changing the capacitance of the delay cell with the usage of IMOS varactor containing two PMOS transistors connected in parallel. The proposed three-stage VCO has been designed with 1.8 V power supply in 180 nm CMOS technology. Capacitance of IMOS varactor has been varied by altering the source/drain voltage Vcontrol and back-gate voltage Vsb of IMOS. The variations in power supply voltage from 1 V to 2.4 V provides output frequency from 1.893 GHz to 7.926 GHz with power dissipation of 0.953 mW to 24.261 mW with IMOS varactor width of 5 µm. The results have been extended for the IMOS width of 10 µm, 15 µm and 20 µm. The tuning range of 122% has been achieved with the power supply tuning method. The variations in source/drain voltage of IMOS from 1 V to 2.4 V provides the output frequency from 6.373 GHz to 5.460 GHz with power dissipation of 9.62 mW. The tuning range of 15.7%, 22.3%, 44% and 40.6% has been obtained for IMOS with widths of 5 μm, 10 μm, 15 μm and 20 μm with the source/drain voltage Vcontrol variations. Further, frequency variation from 5.895 GHz to 6.406 GHz has been obtained with back-gate voltage Vsb tuning of IMOS varactor from 0 V to 2.4 V. The phase noise measured for the VCO is −90.67 dBc/Hz@1 MHz and the figure of merit (FoM) for the VCO is 172.86 dBc/Hz with supply voltage of 1.8 V. Proposed VCO circuit achieved a low power dissipation, wide tuning range, better phase noise and figure of merit (FoM).

A 24 GHz frequency synthesizer for automotive collision avoidance radar

ABSTRACTThis paper describes a 24 GHz frequency synthesizer for automotive collision avoidance radar. This circuit is designed using 65 nm CMOS technology. The voltage-controlled oscillator (VCO) in modified current-reuse configuration where transistors are biased in subthreshold region to save power consumption. The output frequency is 24 GHz, and the reference frequency is 100 MHz. The proposed circuit showed low power consumption of 3.52 mW with the supply voltage of 0.9 V. The VCO tuning range was 7.5% at 24–25.8 GHz, and the VCO also showed a low phase noise of −108.8 dBc @1 MHz and −131.50 dBc @10 MHz. The phase-locked loop showed fast settling time of 3.1 ns with the divider ratio of 240. The proposed circuit showed a low phase noise of −104.32 dBc @1 MHz and −127.02 dBc @10 MHz. Peak-to-peak jitter was 3.5 ps, and rms jitter was 0.754 ps.

Design and Optimization of High Performance K-band Voltage Controlled Oscillator

A high performance voltage-controlled oscillator (VCO) fabricated in TSMC 90nm CMOS process is designed. Design methods of VCO and its buffer are demonstrated. Furthermore, simulation results of VCO are presented. The VCO and its buffer proposed are integrated into a K-band phase-locked loop (PLL). The proposed VCO including buffer consumes only 27mW from a 1.2V power supply and occupies chip area of 540um×360um. The measurement results exhibit phase noise could achieve -93.5dBc/Hz at 1MHz frequency offset. The measured tuning range of VCO is 22.7GHz-28.6GHz.

Switched Substrate-Shield-Based Low-Loss CMOS Inductors for Wide Tuning Range VCOs

A switched substrate-shield inductor (SSI) topology in bulk CMOS is proposed which minimizes parasitic capacitance and substrate losses, while tuned magnetically induced currents facilitate inductor tunability. The high frequency behavior of the induced current is analyzed, resulting in intuitive insights and design guidelines for a high-performance SSI. An SSI prototype in 65-nm bulk CMOS achieves 34% inductance tunability with a quality factor of >10.3. A voltage-controlled oscillator (VCO) using SSI achieves 40.3% tuning range, from 21 to 31.6 GHz, and a phase noise of −119.1 ± 3.7 dBc/Hz at 10-MHz offset frequencies. The VCO core consumes 4.3 ± 0.2 mW from a 1-V supply.

A Low Phase Noise, Low Power and Wide Tuning Range VCO with Filtering Technique in ISM Band

In this paper, a novel voltage controlled oscillator (VCO) with low phase noise, low power consumption and wide tuning range in the industrial, scientific and medical (ISM) band is proposed for communication systems applications. For improving the phase noise, filtering technique is used and VCO is designed with TSMC CMOS 0.18 μm technology and the power supply is 1.5 V. The simulation results with advanced design system (ADS) shows that phase noise in 1 MHz offset frequency from the carrier is -122 dBc/Hz and tuning range is 2 to 2.8 GHz. The power consumption of the core is 2.49 mW.

A Low Phase Noise, Low Power and Wide Tuning Range VCO with Filtering Technique in ISM Band

In this paper, a novel voltage controlled oscillator (VCO) with low phase noise, low power consumption and wide tuning range in the industrial, scientific and medical (ISM) band is proposed for communication systems applications. For improving the phase noise, filtering technique is used and VCO is designed with TSMC CMOS 0.18 μm technology and the power supply is 1.5 V. The simulation results with advanced design system (ADS) shows that phase noise in 1 MHz offset frequency from the carrier is -122 dBc/Hz and tuning range is 2 to 2.8 GHz. The power consumption of the core is 2.49 mW.

Frequency-Tuning Negative-Conductance Boosted Structure and Applications for Low-Voltage Low-Power Wide-Tuning-Range VCO

A frequency-tuning negative-conductance (-G <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">m</sub> ) boosted structure and applications for a voltage-controlled oscillator (VCO) is presented in this paper. Analog tuning varactors connected to a -G <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">m</sub> boosted structure is proposed to significantly alleviate the limitation of the tuning range for the -G <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">m</sub> boosted structure, resulting in a low-voltage low-power wide-tuning-range VCO. Based on the proposed architecture, the fabricated 0.18-μm CMOS VCO exhibits a measured 49.8% tuning range. Operating at 0.65 V low supply voltage, the VCO core consumes 2.37-mW dc power. At this bias condition, the measured average value of phase noise for all frequency ranges is -115.1 dBc/Hz at 1-MHz offset from the carriers. Relative to recently published wide-tuning-range CMOS VCOs, the proposed VCO simultaneously achieves low supply voltage, low dc power dissipation, low phase noise, and a wide tuning range, leading to a good figure-of-merit (FOM) and FOM including the tuning range. Furthermore, formulas of analysis for the proposed frequency-tuning -Gm boosted structure and wide VCO tuning range are presented, and the mechanisms are validated by experiments.

Design of a 60 GHz, 11.7% Tuning-Range Voltage-Controlled Oscillator in 65 nm CMOS Technology

Design of a 60 GHz, 11.7% Tuning-Range Voltage-Controlled Oscillator in 65 nm CMOS Technology

Wide Tuning-Range mm-Wave Voltage-Controlled Oscillator Employing an Artificial Magnetic Transmission Line

A novel technique to extend the tuning range of voltage-controlled oscillators (VCOs) is proposed based on magnetic tuning of a transmission line (TL) resonator. A controllable distributed magnetic coupling in a coplanar strip TL is used to tune the TL parameters in general and the inductance in particular, achieving 222% inductance change of the TL at a center frequency of 60 GHz in order to achieve a wide range of frequency tuning. This technique was implemented with a standard cross-coupled pair oscillator, and an additional varactor. The design was implemented in 65-nm CMOS technology, and achieves a tuning range of 55.1–70.4 GHz (24.6%) with a measured average phase noise of ${-}{\hbox{92.2}}$ dBc/Hz at 1-MHz offset across the entire band. The power consumption is 21.5 mW, including the output buffer. The VCO core area is 50 $\mu$ m $\,\times\,$ 155 $\mu$ m excluding the buffer and 83 $\mu$ m $\,\times\,$ 245 $\mu$ m including the buffer.

Efficient VCO Using FinFET

In this paper the two different architectures of voltage controlled oscillator using MOSFET (Metal Oxide Semiconductor Field Effect Transistor) and FinFET are compared and analyzed. The comparison is on the basis of different parameters of VCO (Voltage Controlled Oscillator). The parameters which are analyzed are Voltage swing, Tuning Range, Power Consumption, number of stages and phase noise. Two architectures of VCO namely Current Starved Ring Oscillator and Source coupled VCO are implemented on Cadence Virtuoso simulator. The results of simulation indicated that implementation using FinFET, gives very high tuning range of VCO as compared to MOSFET. The Tuning range in Current starved VCO using FinFET is found out to be 23 GHz to 32 GHz compared to MOSFET which is only 3 GHz to 6 GHz. The phase noise in Source coupled VCO FinFET is better than MOSFET for low frequency domain. According to power consumption analysis, Source coupled VCO FinFET is much better than Source coupled MOSFET.

A Forwarded-Clock Receiver With Constant and Wide-Range Jitter-Tracking Bandwidth

A source synchronous architecture with constant and wide jitter-tracking bandwidth (JTB) is presented. The proposed receiver is based on an injection-locked oscillator (ILO), which provides jitter filtering and phase deskew simultaneously. While using only the ILO has intrinsic two dependence problems (JTB versus deskew and JTB versus a voltage-controlled oscillator tuning range required for 1 unit interval deskew), the proposed receiver makes them independent. Therefore, the proposed receiver can achieve the optimal JTB in a wide range supporting various applications by controlling deskew phase and JTB independently. A test chip was implemented to prove 11-Gb/s data recovery with constant 70-MHz to 1-GHz JTB in 0.13-μm CMOS.

Low Phase Noise and Wide Tuning Range VCO Using the MOS Differential Amplifier with Active Load

We demonstrate the design of a novel voltage-controlled oscillator (VCO), which is based on a metal-oxide-semiconductor field-effect transistor (MOS) differential amplifier with active load. This VCO achieves low phase noise and wide tuning range. The phase noise is –120 dBc/Hz at 600 KHz offset from a 1.216 GHz carrier frequency. This value is comparable to that of a LC-based integrated oscillator. The operating frequency can be tuned from 117 MHz to 1.216 GHz with the supply voltage varying from 1.3 V to 3.3 V. Therefore, the tuning range is about 90.38% which is larger than most of the LC and ring oscillator. The VCO circuit, which is constructed using a standard 0.35 μm CMOS technology, occupies only 26.25 × 7.52 μm2 die area and dissipated 10.56 mW under a 3.3 V supply voltage.

Design a Low Noise 5GHz Differential Cross-Coupled VCO and Colpitts VCO Using BiCMOS Technology

This paper describes the 0.35 um SiGe BiCMOS Voltage Controlled Oscillators (VCOs). One is Cross-coupled VCO, and the other one is Colpitts VCO. Both of them are designed with the same method. For achieving lower noise, the differential structure was used at this design. The center frequency for Cross-coupled VCO and Colpitts VCO is 5GHz. The tuning range of Cross-coupled VCO and Colpitts VCO is 1750 MHz and 230 MHz, respectively. The phase noise and the figure of merit (the FOM) for Cross-coupled VCO, are -155.5 dBc/Hz and -224.7dBc/Hz @1MHz offset frequency at an oscillation frequency of 5GHz, respectively. The phase noise and the figure of merit value of Colpitts VCO is -134.1 dBc/Hz and -200.3 dBc/Hz at the 1MHz offset from the center frequency of 5GHz. For The DC current of Cross-coupled and Colpitts VCO is 2 mA and 4 mA , respectively. Considering a 3.0 V supply Cross-coupled voltage (VCC) for both VCOs. The output power of Cross-coupled VCO is -3.94 dBm and the Colpitts VCO achieves an output power of 5.428 dBm. Agilent ADS software is used throughout this work

A 54–862-MHz CMOS Transceiver for TV-Band White-Space Device Applications

A 54-862-MHz single-chip CMOS transceiver with a single LC voltage-controlled oscillator (VCO) fractional- <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">N</i> synthesizer is developed for TV-band white-space communications and cognitive radio applications. The transceiver is based on a single-conversion zero-IF architecture with integrated harmonic filtering capability. A combined harmonic rejection mixer and coarse RF tracking filter significantly lessens the in-band harmonic emission problem in the transmitter, as well as the harmonic mixing problem in the receiver. A fractional- <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">N</i> phase-locked loop (PLL) with only a single LC VCO and a wideband multimodulus local oscillator (LO) generator seamlessly covers the entire band. A wideband semi-dynamic divide-by-1.5 circuit is adopted in the LO generator to reduce the VCO tuning range requirement by 25 %. A pseudoexponential capacitor bank structure in the LC VCO substantially reduces the <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">K</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">VCO</sub> and <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">f</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">step</sub> variations across the total band, which is beneficial for maintaining the PLL loop stability and dynamics over the wide band. The transceiver is implemented in 0.18-μ m CMOS, and operates with a single 1.8-V supply. The transmitter delivers a nominal output power of -3 dBm, and exhibits OP <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1 dB</sub> of >; +6.4 dBm, OIP <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> of >; +15.9 dBm, and error vector magnitude (EVM) of <; -34.7 dB for 64-QAM signal. The image and carrier leakage calibration circuits suppress the leakage components below -41 dBc across the entire band. The receiver achieves about 100-dB gain dynamic range, 3.5-6.9-dB noise figure, <; -29-dB EVM, and -43.4/-59.7-dBc third/fifth harmonic mixing suppression. The synthesizer and LO generator achieves the integrated phase noise <; 0.8 rms degree over the entire band.

A low-power low-phase-noise wide-tuning-range K-band VCO in 0.18-.MU.m CMOS

A low-phase-noise wide-tuning-range K-band voltage-controlled oscillator (VCO) is presented in this paper. By employing accumulation MOS (AMOS) varactors deposited between drain and source terminations of the cross-coupled pair, the tuning mechanism are enhanced, leading to a boosted VCO tuning range. Moreover, the phase noise can be improved due to the better cyclostationary noise property. Based on this architecture, the fabricated VCO in 0.18-µm CMOS exhibits a measured 18.2% tuning range. Operating at 0.6-V supply voltage, the VCO consumes 2.28-mW dc power excluding the buffers. The measured phase noise is -112.53dBc/Hz at 1-MHz offset from 24.68-GHz oscillation frequency. Compared to the recently published K-band 0.18-µm CMOS VCOs, it is observed that the proposed VCO can simultaneously achieve low phase noise, wide tuning range, and low dc-power dissipation.