标签: locked

A155-MHzclockrecoverydelayandphaselockedloopA155-MHzClockRecoveryDelay-andPhase-LockedLoopThomasH.Lee,Member,IEEE,andJohnF.Bulzacchelli,StudentMember,IEEEAbstract-Thispaperdescribesacompletelymonolithicdelay-lockedloop(DLL)thatmaybeusedeitherbyitselfasadeskewingelement,orinconjunctionwithanexternalvoltagecontrolledcrystaloscillator(VCXO)toformadelay-andphaselockedloop(DlPLL).Byphaseshiftingtheinputdataratherthantheclock,theDLLandDlPLLprovidejitter-peaking-freeclockrecovery.Additionally,thejittertransferfunctionoftheDlPLLhasalowbandwidthforgoodjitterfilteringwithoutcompromisingacquisitionspeed.TheDlPLLdescribedhereexhibitslessthan1"rmsjitterontherecoveredclock,independentoftheinputdatadensity.Nojitterpeakingisobse……

DesignMethodologyforRFCMOSPhaseLockedLoopsDesignMethodologyforRFCMOSPhaseLockedLoopsForalistingofrecenttitlesintheArtechHouseMicrowaveLibrary,turntothebackofthisbook.DesignMethodologyforRFCMOSPhaseLockedLoopsCarlosQuemadaGuillermoBistueigoAdinInLibraryofCongressCataloging-in-PublicationDataAcatalogrecordforthisbookisavailablefromtheU.S.LibraryofCongress.BritishLibraryCataloguinginPublicationDataAcataloguerecordforthisbookisavailablefromtheBritishLibrary.ISBN-13:978-1-59693-383-5CoverdesignbyYekaterinaRatner2009ARTECHHOUSE685CantonStreetNorwood,MA02062Allrightsreserved.PrintedandboundintheUnitedStatesofAmerica.Nopartofthisbookmaybereproducedorutilizedinanyformorbyanymeans,electronicormechanical,……

PhaseLockedLoopOscillatorPhaseLockedLoopOscillator(PLLOsc.)1.基本组成[pic]VCO:VoltageControlOscillator---OutputfrequencychangeswithcontrolvoltageTherearetwokindsofVCO:[pic]PD:PhaseDetector---ComparethephasedifferencebetweenVCOandreferenceosc.可以用平衡混频器和乘法器作PD.Vo∝⊿│Ψ1-Ψ2┃运算放大器和低通滤波器（环路滤波器）：用来放大PD的输出，同时滤除高次谐波。•PLL的主要目的是将一个不稳的振荡器相位锁定在一个稳定的参考源上。•PLL的环路滤波器的带宽影响锁定时间和杂波抑制。•PLL是一个负反馈环路，设计和维修时一定要注意反馈的极性。尤其是运算放大器的输入端。•检查环路特性可以用开环的形式：从VCO的控制端断开，外加一控制电压。当改变控制电压时，运算放大器的输出应有一个转折点。•PLL的开环直流增益可以认为是无穷大。2.PLL的演变1.提高输出频率：为了把高频振荡器锁定在一低频的参考源上，在环路中加入分频器或倍频器。Fo=N×FrorFo=M×Fr输出频率的改变都必须改变参考源的频率。[pic][pic]2.为了使输出频率容易改变，采用了频率综合的概念。[pic]Fo=(P×B+A)×Fr……