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1、病房呼叫系统外文文献医疗病房呼叫系统外文翻译文献导读:就爱阅读网友为您分享以下“医疗病房呼叫系统外文翻译文献”的资讯，希望对您有所帮助，感谢您对92to.com的支持！AT89C52canbeprogrammedaccordingtoconventionalmethods,canalsobeprogrammedonline.Itmakesthegeneral-purposemicroprocessorandFlashmemorytogether.Inparticular,theFlashmemorycanberepeatedlyerasedcaneffectivelyreducethede
2、velopmentcosts[4].Basedontheabovefactors,thehostandextensioncontrolchipselectAT89C52,canfullymeetvariousneedsofthesystem.B.DesignofthepowerlinecarriercircuitThepowerlinecarriercircuitmainlyincludesapowerlinecouplingcircuit,thesignalreceivingcircuitandsignaltransmittingcircuit,itsendsandreceivesthe
3、powerlinecarriersignal.SchematicisshowninFig.2.Thecoupledcircuitthatistransformer-coupledcoilTZinFig.2,istheoutputandinputchannelforthecarriersignal,andplaytheroleofisolationfrequency220V/50Hz[5].Signalreceivingcircuit:ThecouplingcoilcouplesthecarriersignalreceivedformthepowerlinetobothendsatDl，Cl
4、ampedbyDl，thestartinglevelofthesignalisatafixedvalue,andtopreventexcessiveinrushcurrent.C2,C3andL2constituteaparallelresonantcircuitwhoseresonantfrequencyis120kHz.The120kHzsignalintheinputweaksignalisselectedfrequencyandamplifiedinordertoimprovethesensitivityofthereceivedsignal.ItissenttotheSIGinp
5、ortofchipPL2102,thecarriersignalreceivedbyPL2102demodulatesthedatabitinformationafterbeingtreatmentin・house，thedatabitinformationisoutputtothehostandextensioncontrolchipbyRXDTXDport,meanwhile,HEADsyncoutputslowlevel.Signaltransmittingcircuit:Itincludesthepoweramplifler,thefiltershapingcircuitandth
6、ecompositepipecomplementarysymmetrypowerampliflercircuitcomprisedofVI，V2,V3,andV4.ItampliflesthepowerofthecarriermodulationsignaloutputtedbyPL2102'sPSKOUTport.ItisaddedtothecouplingcoilafterfilteringintegerbyClandLI,andisfedintothepowerlinethroughthecouplingcoil.Thecarriermodulationsignaloutpu
7、ttedbyPL2102isamplifledthroughthepoweramplifiercircuit,filteroutsignalnoiseandfalsesignal.CapacitorCl,inductorLI(18uH/200mA)oftheintegralfiltercircuitareusedtoadjusttheemissioncurrentandwaveform,reducingClandincr
