用于数字电视调谐器的宽带CMOS频率综合器

介绍了一块用于数字电视调谐器的CMOS宽带频率综合器。该频率综合器集成了压控振荡器（VCO）、分频器（Divider）、鉴频鉴相器／电荷泵（PFD／CP）及4MHz晶振电路和整形电路。该芯片使用经典的单变频三波段结构，VCO通过片外谐振回路产生了从80MHz到840MHz的本振信号。为了保证频率综合器在很宽的频带内能正常工作并具有较为一致的性能，设计中VCO模块采用了独创的稳幅机制，并对预分频器结构进行了改进。该芯片采用了3．3V 0．35μm CMOSRF工艺，所有电压信号路径均采用了差分结构，满足了DVB-C QAM64数字电视的低噪声要求，实现了清晰的数字电视接收，文章最后给出了测试结果。     

数字电视调谐器中低噪声LC VCO的设计

给出了基于0.25μm CMOS工艺的数字电视调谐芯片中宽带低噪声LC VCO的设计,通过对VCO谐振网络的优化设计,显著抑制了flick噪声对相位噪声的影响,使三个波段的VCO的相位噪声有了明显改善,文中重点讨论了中波段VCO谐振网络的设计方法并给出中波段的相位噪声的仿真和测试结果。结果显示在中波段偏移中心频率10k处的相噪能改善5~10dBc,整个中波段相位噪声低于-85dBc/Hz@10kHz,频率覆盖190~530MHz。     

全集成低噪声CMOS宽带分数分频频率综合器

设计了一款应用于CMMB数字电视广播接收的全集成低噪声宽带频率综合器。采用三阶ΣΔ调制器小数分频器完成高精度的频率输出,使用仅一个低相位噪声的宽带VCO输出频率范围覆盖900~1 600 MHz,产生的本振信号覆盖UHF的数字电视频段(470~790 MHz)。设计中的频率综合器能在所有的频道下保证环路的稳定以及最小的环路性能偏差。测试结果表明,整个频率综合器的带内相位噪声小于-85 dBc/Hz,并且带外相位噪声在1MHz时均小于-121 dBc/Hz,总的频率综合器锁定时间小于300μs。设计在UMC 0.18μm RFCMOS工艺下实现,芯片面积小于0.6 mm2,在1.8 V电源电压的测试条件下,总功耗小于22 mW。     

一种2 μm GaAs HBT低相噪宽带VCO

提出了一种2 μm GaAs HBT工艺的低相噪宽带压控振荡器(VCO)。与CMOS工艺相比,采用HBT工艺设计的VCO噪声性能更好,具有较大的电流放大倍数和跨导。该VCO采用差分 Colpitts 结构,并对无源器件进行结构优化,在4.1 GHz处,片上螺旋电感的品质因数超过21,实现了较低的相位噪声。通过二极管组成变容阵列,实现了较宽的调谐范围。流片测试结果表明,VCO 调谐范围为3.370~4.147 GHz,最大输出功率为－16.13 dBm,直流功耗为43 mW。在振荡频率为 4.1 GHz 时,相位噪声为－125.2 dBc/Hz@1 MHz。该VCO在相对较宽的调谐范围内实现了较低的相位噪声。     

UHF RFID阅读器中低噪声Σ小数频率综合器的设计

采用0.18μmRF CMOS工艺结合EPC C1G2协议和ETSI规范要求,实现了一种应用于CMOS超高频射频识别阅读器中的低噪声ΔΣ小数频率综合器。基于三位三阶误差反馈型ΔΣ解调器,采用系数重配技术,有效提高频率综合器中频段噪声性能;关键电路VCO的设计过程中采用低压差调压器技术为VCO提供稳定偏压,提高了VCO相位噪声性能。多电源供电模式下全芯片偏置电流为9.6mA,测得在中心频率频偏200kHz、1MHz处,相处噪声分别为-108dBc/Hz和-129.8dBc/Hz。     

一种宽分频范围的CMOS可编程分频器设计

设计了一种基于双模预分频的宽范围可编程分频器。对预分频器的逻辑电路进行了改进,提高了最高工作频率,同时,引入输入缓冲级,增加了低频时分频器的输入敏感性。基于Chartered 0.25μm厚栅CMOS工艺,在SpectreRF中仿真,分频器可在50MHz～2.2GHz频率范围正常工作。流片测试结果表明,该分频器可正常工作在作为数字电视调谐芯片本振源的PLL中,对80～900MHz的VCO输出信号,实现256～32767连续分频。     

适用于超宽带频率综合器的1.5 V 7.656 GHz正交输出锁相环

本论文实现了频率为7.656GHz全集成正交输出CMOS锁相环。该锁相环可以用作MB-OFDM超宽带频率综合器的一个基本模块。为了使环路快速稳定,该锁相环采用整数型结构,指定输入参考频率为66MHz,并且采用了一个宽带的正交压控振荡器,把两个交叉耦合LC压控振荡器通过底部串联耦合来产生正交载波。在0.18微米CMOS工艺和1.5V电源电压下,该锁相环消耗电流16mA（包含驱动电路）,测得相位噪声在1MHz频偏处为-109 dBc/Hz。其中测得正交压控振荡器的频率调谐范围为6.95GHz至8.73GHz。整个芯片的核心面积为1×0.5mm2。     

低增益变化宽线性范围低噪声压控振荡器设计

应用TSMC 0.18μm CMOS工艺设计了一款低调谐增益变化,恒定调谐曲线间隔,恒定输出摆幅的低功耗低噪声宽带压控振荡器(Voltage Controlled Oscillator,VCO).本振荡器的振荡频率覆盖1.153~1.911GHz(49.5%)范围,相邻调谐曲线的覆盖范围大于50%,调谐增益变化范围为45.5~52.7MHz/V(13.7%),相邻调谐曲线间距变化范围为43.2~45.9MHz(5.9%),VCO输出波形的峰峰值为694~715mV(3%),调谐曲线的线性范围为0.2~1.6V(1.4V).在1.8V的电源电压下,VCO在中心频率1.53GHz处耗电电流为3.2mA,相位噪声在1MHz频偏处为-130.5dBc/Hz,FOM值为-186.5dBc/Hz.     

一种UHF频段小数分频频率综合器设计与实现

基于130 nm CMOS工艺设计了一款特高频(UHF)频段的锁相环型小数分频频率综合器.电感电容式压控振荡器(LC VCO)片外调谐电感总值为2 nH时,其输出频率范围为1.06～1.24 GHz,调节调谐电感拓宽了频率输出范围,并利用开关电容阵列减小了压控振荡器的增益.使用电荷泵补偿电流优化了频率综合器的线性度与带内相位噪声.此外对电荷泵进行适当改进,确保了环路的稳定.测试结果表明,通过调节电荷泵补偿电流,频率综合器的带内相位噪声可优化3 dB以上,中心频率为1.12 GHz时,在1 kHz频偏处的带内相位噪声和1 MHz频偏处的带外相位噪声分别为-92.3和-120.9 dBc/Hz.最小频率分辨率为3 Hz,功耗为19.2 mW.     

基于ADF4351的频率合成器设计

首先介绍了锁相环的基本原理,再介绍一个集成VCO的宽带频率合成器芯片ADF4351,并用该芯片设计一个输出为154.8MHz^212.775MHz的频率合成器,实测其相位噪声和杂散指标都能很好满足设计要求,能满足多种通信系统对信号源的需求。     

A 1-V 9.7-mW CMOS Frequency Synthesizer for IEEE 802.11a Transceivers

A 1-V CMOS frequency synthesizer is proposed for wireless local area network 802.11a transceivers using a novel transformer-feedback voltage-controlled oscillator (VCO) for low voltage and a stacked frequency divider for low power. Implemented in a 0.18-mum CMOS process and operated at 1-V supply, the VCO measures a phase noise of -140.5 dBc at an offset of 20 MHz with a center frequency of 4.26 GHz and a power consumption of 5.17 mW. Its tuning range is as wide as 920 MHz (23%). By integrating the VCO into a frequency synthesizer, a phase noise of -140.1 dBc/Hz at an offset of 20 MHz is measured at a center frequency of 4.26 GHz. Its output frequency can be changed from 4.112 to 4.352 GHz by switching the 3-bit modulus of the programmable divider. The synthesizer consumes only 9.7 mW and occupies a chip area of 1.28 mm².     

具有自校准压控振荡器和精确自动频率校准算法的低噪声频率合成器

A low noise phase locked loop （PLL） frequency synthesizer implemented in 65 nm CMOS technology is introduced. A VCO noise reduction method suited for short channel design is proposed to minimize PLL output phase noise. A self-calibrated voltage controlled oscillator is proposed in cooperation with the automatic frequency calibration circuit, whose accurate binary search algorithm helps reduce the VCO tuning curve coverage, which reduces the VCO noise contribution at PLL output phase noise. A low noise, charge pump is also introduced to extend the tuning voltage range of the proposed VCO, which further reduces its phase noise contribution. The frequency synthesizer generates 9.75-11.5 GHz high frequency wide band local oscillator （LO） carriers. Tested 11.5 GHz LO bears a phase noise of-104 dBc/Hz at 1 MHz frequency offset. The total power dissipation of the proposed frequency synthesizer is 48 mW. The area of the proposed frequency synthesizer is 0.3 mm^2, including bias circuits and buffers.     

一种用于短距离器件的带自校准的∑-Δ分数分频频率综合器

介绍了一种应用于433/868MHz频段短距离器件的分数分频频率综合器.采用带自适应频率校准的宽带压控振荡器来覆盖要求的频段,并采用3位量化、3阶的Σ△调制器来实现分数分频和改善锁相环的带外噪声.测试结果表明,自适应频率校准能够正常工作,压控振荡器的频率调节范围为1.31～1.18GHz,在3MHz频偏处的带外噪声为-139dBc/Hz,分数毛刺低于-60dBc.芯片采用0.35μm CMOS工艺,芯片面积仅为1.8mm2,功耗仅为57mW.     

A low jitter 0.3-165 MHz CMOS PLL frequency synthesizer for 3 V/5 Voperation

This paper describes a phase-locked loop (PLL) based frequency synthesizer. The voltage-controlled oscillator (VCO) utilizing a ring of single-ended current-steering amplifiers (CSA) provides low noise, wide operating frequencies, and operation over a wide range of power supply voltage. A programmable charge pump circuit automatically configures the loop gain and optimizes it over the whole frequency range. The measured PLL frequency ranges are 0.3-165 MHz and 0.3-100 MHz at 5 V and 3 V supplies, respectively (the VCO frequency is twice PLL output). The peak-to-peak jitter is 81 ps (13 ps rms) at 100 MHz. The chip is fabricated with a standard 0.8-μm n-well CMOS process     

A fully integrated direct-conversion digital satellite tuner in 0.18μm CMOS

A fully integrated direct-conversion digital satellite tuner for DVB-S/S2 and ABS-S applications is presented.A broadband noise-canceling Balun-LNA and passive quadrature mixers provided a high-linearity low noise RF front-end,while the synthesizer integrated the loop filter to reduce the solution cost and system debug time.Fabricated in 0.18μm CMOS,the chip achieves a less than 7.6 dB noise figure over a 900-2150 MHz L-band, while the measured sensitivity for 4.42 MS/s QPSK-3/4 mode is -91 dBm at the PCB connector.The fully integrated integer-N synthesizer operating from 2150 to 4350 MHz achieves less than 1℃integrated phase error. The chip consumes about 145 mA at a 3.3 V supply with internal integrated LDOs.     

A 2 V 1.8 GHz fully integrated CMOS dual-loop frequency synthesizer

A 2 V 1.8 GHz fully integrated CMOS dual-loop frequency synthesizer is designed in a standard 0.5 /spl mu/m digital CMOS process for wireless communication. The voltage-controlled oscillator (VCO) required for the low-frequency loop is designed using a ring-type VCO and achieves a tuning range of 89% from 356 to 931 MHz and a phase noise of -109.2 dBc/Hz at 600 kHz offset from 856 MHz. With an active chip area of 2000/spl times/1000 /spl mu/m/sup 2/ and at a 2 V supply voltage, the whole synthesizer achieves a tuning range from 1.8492 to 1.8698 GHz in 200 kHz steps with a measured phase noise of -112 dBc/Hz at 600 kHz offset from 1.86 GHz. The measured settling time is 128 /spl mu/s and the total power consumption is 95 mW.     

使用三位三阶Δ∑调制器的集成1GHz小数频率合成器

本文实现了一个采用三位三阶Δ∑调制器的高频谱纯度集成小数频率合成器.该频率合成器采用了模拟调谐和数字调谐组合技术来提高相位噪声性能,优化的电源组合可以避免各个模块之间的相互干扰,并且提高鉴频鉴相器的线性度和提高振荡器的调谐范围.通过采用尾电流源滤波技术和减小振荡器的调谐系数,在片压控振荡器具有很低的相位噪声,而通过采用开关电容阵列,该压控振荡器达到了大约100MHz的调谐范围,该开关电容阵列由在片数字调谐系统进行控制.该频率合成器已经采用0.18μm CMOS工艺实现,仿真结果表明,该频率频率合成器的环路带宽约为14kHz,最大带内相位噪声约为-106dBc/Hz;在偏离载波频率100kHz处的相位噪声小于-120dBc/Hz,具有很高的频谱纯度.该频率合成器还具有很快的反应速度,其锁定时间约为160μs.     

A 5-GHz CMOS Frequency Synthesizer With an Injection-Locked Frequency Divider and Differential Switched Capacitors

A phase-locked loop (PLL)-based frequency synthesizer at 5 GHz is designed and fabricated in 0.18-${rm mu}hbox{m}$ CMOS technology. The power consumption of the synthesizer is significantly reduced by using an injection-locked frequency divider (ILFD) as the first frequency divider in the PLL feedback loop. The synthesizer chip consumes 18 mW of power, of which only 3.93 mW is consumed by the voltage-controlled oscillator (VCO) and the ILFD at 1.8-V supply voltage. The VCO has the phase noise of $-$ 104 dBc/Hz at 1-MHz offset and an output tuning range of 740 MHz. The chip size is 1.1 mm $times$ 0.95 mm.      

A low phase noise and low power 3–5 GHz frequency synthesizer in 0.18 µm CMOS technology

A low power frequency synthesizer for WLAN applications is proposed in this paper. The NMOS transistor-feedback voltage controlled oscillator (VCO) is designed for the purpose of decreasing phase noise. TSPC frequency divider is designed for widening the frequency range with keeping low the power consumption. The phase frequency detector (PFD) with XOR delay cell is designed to have the low blind and dead zone, also for neutralizing the charge pump (CP) output currents; the high gain operational amplifier and miller capacitors are applied to the circuit. The frequency synthesizer is simulated in 0.18 µm CMOS technology while it works at 1.8 V supply voltage. The VCO has a phase noise of −136 dBc/Hz at 1 MHz offset. It has 10.2% tuning range. With existence of a frequency divider in the frequency synthesizer loop the output frequency of the VCO can be divided into the maximum ratio of 18. It is considered that the power consumption of the frequency synthesizer is 4 mW and the chip area is 10,400 µm².