Avago ALM-1712 GPS 低噪音放大方案

AvagoALM-1712GPS低噪音放大方案Avago公司的ALM-1712是GPS低噪音放大器前端模块，它把低噪音放大器(LNA)和GPSFBAR滤波器组合在一起.ALMT712采用先进的GaAsE-pHEMT和FBAR技术,具有非常低的噪音,典型值为1.65dB,关断电六小于luA,RF输入引脚的ESD大于3KV,电源电压可低到1.0V,并能通过单一外接电阻调整偏压电流.本文介绍了ALMT712的主要特性，演示板和应用电路框图，演示板元件布局图和所用元件表以及S参数和测量参考平面.ALM-1712:GPSLow-NoiseAmplifierFront-endModulewithIntegratedPreandPostFiltersandVariableCurrent/ShutdownFunctionAvagoTechnologies,ALM-1712isaGPSfront-endmodulethatcombinesalow-noiseamplifier(LNA)withGPSFBARfilters.TheLNAusesAvagoTechnologies'proprietaryGaAsEnhancement-modepHEMTprocesstoachievehighgainwithverylownoisefigureandhighlinearity.Noisefiguredistributionisverytightlycontrolled.ACMOS-compatibleshutdownpinisincludedeitherforturningtheLNAon/off,orforcurrentadjustment.TheintegratedfilterutilizesanAvagoTechnologies'leading-edgeFBARfilterforexceptionalrejectionatCell/PCS-Bandfrequencies.Thelownoisefigureandhighgain,coupledwithlowcurrentconsumptionmakeitsuitableforuseincriticallow-powerGPSapplicationsorduringlow-batterysituations.ALM-1712主要特性：VeryLowNoiseFigure:1.65dBtypExceptionalCell/PCS-BandrejectionAdvancedGaAsE-pHEMT&FBARTechnologyLowexternalcomponentcountShutdowncurrent:<1uACMOScompatibleshutdownpin(SD)ESD:>3kVatRFinpin1mmtypicalthicknessAdjustablebiascurrentviasingleexternalresistor/voltageUseabledownto1.OVsupplyvoltageSmallpackagedimension:4.5(L)x2.2(W)xl(H)mm3MeetsMSL3,Lead-freeandhalogenfreeSpecifications(Typicalperformance@25°C)At1.575GHz,Vdd=2.7V,Tdd=8.OmAGain=12.8dBNF=1.65dBIIP3=+7dBm,IPldB=+3dBmSU=-9dB,S22=-10dBCell-BandRejection:95dBcPCS-BandRejection:90dBcALMT712应用：GPSFront-endModu1e图1.ALM-1712应用电路图2.ALM-1712演示板和应用电路框图DCPin(on耍rationof4*pin<onne<torPinspointingoutofthepagePins1,4=GNDPinspointingoutofthepagePins1,4=GNDPin2=Sh«tdowi($D)Pin3=VddSupply图3.ALM-1712演示板元件布局图表1.演示板和应用电路元件表CircuitSymbolSizeDescriptionLI040222nHInductor(TaiyoYudenHK1OO522NJ-T)L204026^nHInductor(Tai/oYudenHK10056N8J-T)C108050.1uFCapacitor(MurataGRM188R71C1O4KA0ID)C2040215pFCapacitor(KyoceraCA4O5CH150AHF)C304026.8pFCapacitor(KyoceraCM05cH6R8c50AHF)Ri040212