Wide tuning-range CMOS VCO based on a tunable active inductor

In this paper, a wide tuning-range CMOS voltage-controlled oscillator (VCO) with high output power using an active inductor circuit is presented. In this VCO design, the coarse frequency is achieved by tuning the integrated active inductor. The circuit has been simulated using a 0.18-µm CMOS fabrication process and presents output frequency range from 100 MHz to 2.5 GHz, resulting in a tuning range of 96%. The phase noise is –85 dBc/Hz at a 1 MHz frequency offset. The output power is from –3 dBm at 2.55 GHz to +14 dBm at 167 MHz. The active inductor power dissipation is 6.5 mW and the total power consumption is 16.27 mW when operating on a 1.8 V supply voltage. By comparing this active inductor architecture VCO with general VCO topology, the result shows that this topology, which employs the proposed active inductor, produces a better performance.     

A Wide Tuning Range Voltage Controlled Oscillator with a High Tunable Active Inductor

This paper presents a wide tuning range CMOS voltage controlled oscillator (VCO) with a high-tunable active inductor circuit. In this VCO circuit, the coarse frequency is achieved by tuning the integrated active inductor circuit. The VCO circuit is designed in 0.18  \(\upmu \hbox {m}\) CMOS process and simulated with Cadence Spectra. The simulation results show the frequency tuning range from 120 MHz to 2 GHz resulting in a tuning range of 94 %. The phase noise variation is from \(-\) 80 to \(-\) 90 dBc/Hz at a 1 MHz frequency offset, and output power variation is from \(-\) 4.7 to \(+\) 11.5 dBm. The active inductor power consumption is 2.2 mW and the total power dissipation is 7 mW from a 1.8 V DC power supply. By comparing the proposed VCO circuit with the general VCO topology, the results show that this VCO architecture by using the novel, high-tunable and low power active inductor circuit, presents a better performance regarding low chip size, low power consumption, high tuning range and high output power.     

A 1.9-GHz CMOS VCO with micromachined electromechanically tunablecapacitors

This paper presents a 1.9-GHz CMOS voltage-controlled oscillator (VCO) where the resonant circuit consists of micromachined electromechnically tunable capacitors and a bonding wire inductor. The tunable capacitors were implemented in a MUMP's polysilicon surface micromachining process. These devices have a nominal capacitance of 2.1 pF and a quality factor (Q-factor) of 9.3 at 1.9 GHz. The capacitance is variable from 2.1 pF to 2.9 pF within a 4-V control, voltage range. The active circuits were fabricated in a 0.5-μm CMOS process. The VCO was assembled in a ceramic package where the MUMP's and CMOS dice were bonded together. The experimental VCO achieves a phase noise of -98 dBc/Hz and -126 dBc/Hz at 100 kHz and 600 kHz offsets from the carrier, respectively. The tuning range of the VCO is 9%. The VCO circuit and the output buffer consume 15 mW and 30 mW from a 2.7-V power supply, respectively     

A Novel Broad-Band MMIC VCO Using an Active Inductor

This paper proposes a novel broad-band MMIC VCO using an active inductor. This VCO is composed of a serial resonant circuit, in which the capacitor is in series with an active inductor that has a constant negative resistance. Since the inductance value of this active inductor is inversely proportional to the square of the transconductance and can vary widely with the FETs gate bias control, a broad-band oscillation tuning range can be obtained. Furthermore, since this active inductor can generate a constant negative resistance of more than 50 , the proposed VCO can oscillate against a 50- output load immediately without using additional impedance transformers. We have fabricated the VCO using a GaAs MESFET process. A frequency tuning range of more than 50%, from 1.56 to 2.85 GHz, with an output power of 4.4±1.0 dBm, was obtained. With a carrier of 2.07 GHz, the phase noise at 1-MHz offset was less than –110 dBc/Hz. The chip size was less than 0.61 mm², and the power consumption was 80 mW. This broad-band analog design can be used at microwave frequencies in PLL applications as a compact alternative to other types of oscillator circuits.     

Wide tunable CMOS active inductor

A tunable CMOS active inductor is presented. The circuit uses a crosscoupled pair of transistors providing positive feedback for enhanced quality factor. The circuit is biased with a controllable current source varying the feedback and tuning the inductor. The proposed inductor is designed and simulated in a 90 nm digital CMOS process. It shows a wide-frequency range inductive impedance and a very high resonance frequency. By cascading two inductors, a wideband filter/ amplifier is designed to characterise the inductor performance.     

A 1.8-2.6 GHz CMOS VCO with switched capacitor array and switched inductor array

The design of a 1.76-2.56 GHz CMOS voltage-controlled oscillator(VCO)with switched capacitor array and switched inductor array is presented.Fabricated in 0.18μm 1P6M CMOS technology,the VCO achieves a 37% frequency tuning range.The measured phase noise varies between-118.5 dBc/Hz and-122.8 dBc/Hz at 1 MHz offset across the tuning range.Power consumption is about 14.4 mW with a 1.8 V supply.Based on a reconfigurable LC tank with switched capacitor array and switched inductor array,the mnmg range is analyzed and derived in terms of design parameters,yielding useful equations to guide the circuit design.     

A novel self-oscillating HEMT-HBT cascode VCO-mixer using an activetunable inductor

Here we describe a unique Ka-band self-oscillating HEMT-HBT cascode mixer design which integrates an active tunable resonator circuit. The VCO-mixer MMIC integrates GaAs HEMT's and HBT's using selective molecular beam epitaxy (MBE) technology. The HEMT-HBT cascode active mixer operates similarly to a dual-gate mixer. The HBT of the cascode is used to construct a VCO by presenting the base with an HEMT tunable active inductor. The VCO can be tuned from 28.5 to 29.3 GHz while providing ≈0 dBm of output power. Operated as an upconverter, the MMIC achieves 6-9 dB conversion loss over a 31-39 GHz output frequency band. Using these active approaches, both VCO and mixer functions were integrated into a compact 1.44×0.76 mm² chip area. The active RF integrated circuit (IC) techniques presented here have direct implications to future high complexity millimeter-wave monolithic integrated circuits (MIMICs) for ultrahigh-speed clock recovery and digital radio applications     

Floating active inductor based Class-C VCO with 8 digitally tuned sub-bands

A fully integrated floating active inductor based voltage-controlled oscillator (VCO) is presented. The active inductor employs voltage differencing transconductance amplifier (VDTA) as a building block. The designed VCO achieves frequency tuning by varying the bias current through the VDTA and utilizes a Class-C topology for improving the phase noise performance. The inductor-less VCO is designed and implemented in a 45-nm CMOS process and its performance is estimated using Virtuoso ADE of Cadence. Operating at a supply voltage of ±1 V, the proposed VCO consumes 0.44–1.1 mW corresponding to the oscillation frequency of 1.1–1.8 GHz thereby exhibiting a tuning range of 48.27%. The phase noise of the VCO lies in the range of −94.12 to −98.37 dBc/Hz at 1 MHz offset resulting in a FOM of −172.14 to −176.69 dBc/Hz.     

A 38% Tuning Bandwidth Low Phase Noise Differential Voltage Controlled Oscillator Using a 0.5 $mu$m E/D-PHEMT Process

This paper presents a 38% tuning bandwidth low phase noise differential voltage controlled oscillator (VCO) using a 0.5 $mu$m enhancement/depletion-pseudomorphic high-electron mobility transistor (E/D-PHEMT) process. The proposed VCO is based on a differential topology with two common-gate transistors. To achieve a wide tuning range with low phase noise, varactor in the VCO core employs the E-mode PHEMT device. The frequency of the VCO is from 18.8 to 27.5 GHz with a tuning bandwidth of 38% and an output power of higher than 5 dBm. The VCO demonstrates a phase noise of ${-}109$ dBc/Hz at 1 MHz offset frequency. This circuit can be compared with the VCOs fabricated using the advanced InP HBT technologies.      

4.2GHz 1.8V CMOS LC压控振荡器

基于Hajimiri提出的VCO相位噪声模型,分析了差分LC VCO电路参数对于相位噪声的影响。根据前面的分析,详细介绍了LC VCO电路的设计方法:包括高Q值片上电感的设计、变容MOS管的设计以及尾电流的选取。采用SMIC 0.18μm 1P6 M、n阱、混合信号CMOS工艺设计了一款4.2GHz 1.8V LC VCO。测试结果表明:当输出频率为4.239GHz时,频偏1MHz处的相位噪声为-101dBc/Hz,频率调节范围为240MHz。     

一种采用有源电感的可调增益小面积超宽带低噪声放大器

设计了一款采用可调谐有源电感（TAI）的可调增益的小面积超宽带低噪声放大器(LNA),输入级采用共基极结构,输出级采用射随器结构,分别实现了宽带输入和输出匹配;放大级采用带有反馈电阻的共射共基结构以取得宽的带宽,并采用TAI作负载,通过调节TAI的多个外部偏压使LNA的增益可调。结果表明,该LNA在2~9GHz的频带内,通过组合调节有源电感调节端口的偏压可实现S21在16.5~21.1dB的连续可调;S11小于-14.7dB;S22小于-19.3dB;NF小于4.9dB;芯片面积仅为0.049mm2。     

MEMS-Based Tunable LC Bandstop Filter With an Ultra-Wide Continuous Tuning Range

This letter presents a new microelectromechanical system-based tunable LC filter that utilizes a tunable capacitor and a tunable inductor in a single device. An electrically floating metal plate is located between the tunable capacitor and the tunable inductor. As the floating metal plate is thermally moved and used commonly for both the capacitor and inductor, the device provides an ultra-wide continuous frequency tuning range by a simultaneous increase or decrease of the capacitance and inductance. The fabricated tunable LC filter showed a continuous frequency tuning ratio in excess of 127% in a range of 8.8 GHz to more than 20 GHz.      

Millimeter-wave voltage-controlled oscillators in 0.13-/spl mu/m CMOS technology

This paper describes the design of CMOS millimeter-wave voltage controlled oscillators. Varactor, transistor, and inductor designs are optimized to reduce the parasitic capacitances. An investigation of tradeoff between quality factor and tuning range for MOS varactors at 24 GHz has shown that the polysilicon gate lengths between 0.18 and 0.24 /spl mu/m result both good quality factor (>12) and C/sub max//C/sub min/ ratio (/spl sim/3) in the 0.13-/spl mu/m CMOS process used for the study. The components were utilized to realize a VCO operating around 60 GHz with a tuning range of 5.8 GHz. A 99-GHz VCO with a tuning range of 2.5 GHz, phase noise of -102.7 dBc/Hz at 10-MHz offset and power consumption of 7-15mW from a 1.5-V supply and a 105-GHz VCO are also demonstrated. This is the CMOS circuit with the highest fundamental operating frequency. The lumped element approach can be used even for VCOs operating near 100-GHz and it results a smaller circuit area.     

A 0.35-/spl mu/m CMOS 2-GHz VCO in wafer-level package

This letter presents a complementary metal oxide semiconductor (CMOS) voltage-controlled oscillator (VCO) with a high-Q inductor in a wafer-level package for the LC-resonator. The on-chip inductor is implemented using the redistribution metal layer of the wafer-level package (WLP), and therefore it is called a WLP inductor. Using the thick passivation and copper metallization, the WLP inductor has high quality-factor (Q-factor). A 2-nH inductor exhibits a Q-factor of 8 at 2 GHz. The center frequency of the VCO is 2.16 GHz with a tuning range of 385 MHz (18%). The minimum phase noise is measured to be -120.2 dBc/Hz at an offset frequency of 600 kHz. The dc power consumed by the VCO-core is 1.87 mW with a supply voltage of 1.7 V and a current of 1.1 mA. The output power with a 50-/spl Omega/ load is -12.5/spl plusmn/1.3 dBm throughout the whole tuning range. From the best of our knowledge, compared with recently published 2-GHz-band 0.35 /spl mu/m CMOS VCOs in the literature, the VCO in this work shows the lowest power consumption and the best figure-of-merit.     

A V-Band CMOS VCO With an Admittance-Transforming Cross-Coupled Pair

A novel circuit topology suitable for the implementation of CMOS voltage-controlled oscillators (VCOs) at millimeter-wave frequencies is presented in this paper. By employing transmission line segments to transform the admittance of the additional cross-coupled pair, the proposed LC-tank VCO can sustain fundamental oscillation at a frequency close to the $f _{max}$ of the transistors. Using a standard 0.18 $muhbox{m}$ CMOS process, a V-band VCO is realized for demonstration. The fabricated circuit exhibits a frequency tuning range of 670 MHz in the vicinity of 63 GHz. The measured output power and phase noise at 1 MHz offset are $-hbox{15~dBm}$ and $-hbox{89~dBc}/hbox{Hz}$ , respectively. Operated at a 1.8 $~$V supply voltage, the VCO core and the output buffer consume a total DC current of 55 mA.      

1.9～5.7 GHz宽带低噪声BiCMOS LC VCO

设计了一种宽带、低相位噪声差分LC压控振荡器(VCO)。所设计的电路采用开关电容阵列和开关电感,实现了多波段振荡输出。对负阻环节跨导进行了优化设计,将热噪声控制在最小范围内,同时采用高品质因数片上螺旋电感,以减小电路的噪声干扰。采用台积电(TSMC)0.35μmSiGe BiCMOS工艺制作了流片,并进行了仿真和硬件电路实验。实测结果表明,当调谐电压为0～3.3 V时,可设定VCO工作在6个波段(1.9～2.1 GHz,2.1～2.4 GHz,2.4～3.0 GHz,3.0～3.4 GHz,3.4～4.2 GHz,4.2～5.7 GHz),此6波段连续可调,构成了1.9～5.7 GHz宽带VCO;VCO的中心频率为2.4 GHz、偏离中心频率为1 MHz时实测相位噪声为-111.64 dBc/Hz;在3.3 V电源电压下实测核静态电流约为1.8 mA,从而验证了宽带、低噪声BiCMOS LC VCO设计方案之正确性。     

Performance analysis of a low power low noise tunable band pass filter for multiband RF front end

This paper presents a low power tunable active inductor and RF band pass filter suitable for multiband RF front end circuits. The active inductor circuit uses the PMOS cascode structure as the negative transconductor of a gyrator to reduce the noise voltage. Also, this structure provides possible negative resistance to reduce the inductor loss with wide inductive bandwidth and high resonance frequency. The RF band pass filter is realized using the proposed active inductor with suitable input and output buffer stages. The tuning of the center frequency for multiband operation is achieved through the controllable current source. The designed active inductor and RF band pass filter are simulated in 180 nm and 45 nm CMOS process using the Synopsys HSPICE simulation tool and their performances are compared. The parameters, such as resonance frequency, tuning capability, noise and power dissipation, are analyzed for these CMOS technologies and discussed. The design of a third order band pass filter using an active inductor is also presented.     

一种L、S波段微机械压控振荡器

报道了一种中心频率为2GHz的电感电容(LC)压控振荡器,其谐振回路由微机械可变电容和键合线电感构成。微机械可变电容采用与集成电路兼容的表面微机械工艺制造,在2GHz时其Q值约为32.6,当调节电压从0V增大到12V时,电容量变化范围为25%。通过键合技术将微机械可变电容与有源电路集成在一起,制备了MEMSVCO器件,测试结果表明,载波频率为2.004GHz时,VCO的单边带相位噪声为-103.5dBc/Hz@100kHz,输出功率为12.51dBm。调频范围约为4.8%。     

A low-power voltage-controlled oscillator with current-switched technique

A low-power voltage-controlled oscillator (VCO) with current-switched technique is presented. The circuit is implemented in 0.18-μm CMOS technology. In the design, a large inductor is used for low-power and low-phase-noise application, whereas a switched capacitor bank and two pairs of MOS varactors are adopted for coarse tuning and fine tuning respectively. The proposed VCO is biased at the boundary of the current and voltage limited region for a good trade-off between power consumption and phase noise. The phase noise of the proposed VCO is reduced in each sub-band by a current-switched technique, and a phase noise improvement of as much as 2.75 dB has been achieved. The proposed VCO has a measured tuning range of 15.2 % from 4.34 to 5.05 GHz and dissipates an average power of 3.78 mW at 1.2 V supply voltage, whereas its measured phase noise and figure of merit FOM_T are ?113.0 dBc/Hz and ?183.7 at 1 MHz offset from the frequency of 4.36 GHz respectively.     

IOGHz 0.25μm CMOS LC压控振荡器

采用标准0.25μm CMOS工艺实现了10GHz LC压控振荡器.为了适应高频工作,并实现低相位噪声,该压控振荡器采用了手动优化的带中心抽头的对称电感,将A-MOS变容二极管与无源金属-绝缘层-金属电容串联,并采用了带LC滤波器的尾电流源.测试结果显示,当振荡频率为10.2GHz时,在1MHz频偏处相位噪声为-103.2dBc/Hz,调谐范围为11.5%.供电电压为3.3V时,核心电路功耗为9.0mW.芯片面积为0.67mm×0.58mm.