文献翻译——基于AT89C52的LED概述

第1页外文文献资料BasedonAT89C52LEDoverviewLED(LightEmittingDiode),light-emittingdiode,isasolidstatesemiconductordevices,whichcanbedirectlyconvertedintoelectricitytolight.LEDistheheartofasemiconductorchip,thechipisattachedtooneendofastent,isthenegativeside,theotherendofthepowerofthecathode,theentirechippackagetobeepoxyresin.Semiconductorchipiscomposedoftwoparts,partoftheP-typesemiconductor,itinsidethehole-dominated,theothersideistheN-typesemiconductor,hereismainlyelectronic.Butlinkingthetwosemiconductors,amongthemtheformationofaPNjunction.Whenthecurrentthroughthewiresroleinthischip,willbepushinge-P,Pzoneintheholewithelectroniccomposite,andthentobeissuedintheformofphotonenergy,andthisistheprincipleofLEDluminescence.Thewavelengthoflightthatisthecoloroflight,isformedbythePNjunctionofthedecisionsofthematerial.LEDhistory50yearsago,peoplehavetounderstandsemiconductormaterialscanproducelightofthebasicknowledge,thefirstcommercialdiodesin1960.EnglishistheLEDlightemittingdiode(LED)acronym,anditsbasicstructureisanelectroluminescentsemiconductormaterials,placedinawirerack,thensealedwithepoxyresinaround,thatis,solidpackage,Therefore,theprotectionoftheinternalbatteriescanplaytheroleofline,sotheseismicperformanceLEDgood.InstrumentsusedforthefirstLEDlightsourceinstructions,butallkindsoflightcoloredLEDlightsintrafficandlargescreenhasbeenwidelyapplied,haveaverygoodeconomicandsocialbenefits.The12-inchredtrafficlightsasanexample,isusedintheUnitedStateshavelonglife,low-efficiency140wattincandescentlampasalightsource,itproduced2,000lumensofwhitelight.Theredfilter,theloss-90percent,only200lumensofredlight.Inthelightofthenewdesign,Lumiledscompanieshave18redLEDlightsource,includingthelossofcircuit,atotalpowerconsumptionof14wattstogeneratethesameopticaleffect.AutomotiveLEDlightsisalsothesourceofimportantareas.Forgenerallighting,peopleneedmorewhitelightsources.The1998whiteLEDsuccessfuldevelopment.ThisistheGaNLEDchipandYttriumAluminumGarnet(YAG)packagetogethercause.GaNchipoftheBlu-ray(p=465nm,Wd=30nm),madeofhigh-temperaturesinteringoftheCe3+YAGphosphorsexcitedbythisBlu-rayafterirradiatingayellow,thepeak550nm.Blue-chipinstalledintheLED-basedWanxingreflectioninthecavity,coveredwitharesinmixedwithYAGthinlayer,about200-500nm.LED-basedtabletsissuedbytheBlu-rayabsorptionpartofthephosphor,thephosphor第2页anotherpartoftheBlu-rayandayellowlightmixed,canbeawhite.Now,theInGaN/YAGwhiteLED,YAGphosphorbychangingthechemicalcompositionofthephosphorlayerandadjustthethicknessofthe3500-10000Kcolortemperaturecanbecoloredwhite.ThisblueLEDthroughthemethodbywhite,constructedsimple,low-cost,hightechnologyismature,sousethemost.Inthe1960s,theuseofscienceandtechnologyworkerssemiconductorPNjunctionofTheprincipleofdevelopingaLEDlight-emittingdiodes.Atthattime,thedevelopmentofLED,thematerialsusedareGaASP,itsluminouscolorisred.Afternearly30yearsofdevelopment,andnowweareveryfamiliarwiththeLED,hasbeensenttored,orange,yellow,green,blue,andothershade.TheLEDdisplayscreenandvideodisplayintothetextbyLEDmatrixblocks.Graphicdisplaycanbedisplayedwithcomputer,English,Chinesetextandgraphics,Videoscreenusingmicrocomputercontrol,graphic,image,withreal-time,synchronization,clearinformationdisseminationwayplayallkindsofinformation,butalsoshows2d,3danimation,videos,TV,VCDprogramsandlive.TheLEDdisplayscreendisplaybrightcolors,stereosenseisstrong,suchasoil,suchasfilms,widelyusedinfinance,taxation,industryandcommerce,telecommunications,sports,advertising,corporations,transportation,educationsystem,station,port,airport,hospital,shoppingmalls,hotels,Banks,securitiesmarket,market,andconstructionmanagementofindustrialenterprises,Christiesandotherpublicplaces.TheLEDdisplaycandisplaythechangeofdigitalimage;text,graphics,Notonlycanbeusedforindoorenvironmentcanalsobeusedinoutdoorenvironment,projectors,LCDTVwall,andtheincomparableadvantages.TheclassificationoftheLEDdisplay1,thecolorcanbedividedintogezerThesinglecolordisplay:singlecolors(redorgreen).Doublecolors:redandgreenscreen,doublecolorsgray,canshow256levels65536colors.Full-colordisplay:red,green,andblue,graylevel256gezerfull-colordisplayscreencanshowmorethan1,600colors.2,accordingtotheclassificationofdisplaydevicesLEDdigitaldisplay:displaydeviceforsevenyards,suitableformakingtheclockdisplayscreen,interestrates,digitalelectronicdisplayscreen.PicturesofLEDdotmatrixLCDdisplaydeviceiscomposedofmany:evenlycomposedoflightemittingdiodematrixdisplaymodule,suitableforbroadcasttext,imagesofinformation.LEDvideodisplay:displaydeviceiscomposedbymanylight-emittingdiodes,video,animationshowsvariousvideofiles.3,byusingoccasionsclassificationIndoordisplay:lightpointislesser,general3mm-8mm,displayareaof第3页generalseveraltensquaremetersto.Outdoorscreenareatoseveralhundredsquaremetersgeneraldozens,highbrightness,canworkunderthesun,inthewind,rain,waterprooffunction.4points,accordingtotheclassificationoflightindiameterIndoorscreens:3mm,3.75mm,5mm,Outdoorscreen:10mm,12mmand16mm,19mm,20mm,21mm,22mm,26mmThebasicunitofthelightoutdoorscreenforledlightconetube,theprincipleisagroupofred,green,andbluelightemittingdiodesealedinaplastictubeincommon5.Displayhorizontallyscrolling,static,verticalscrollandflipshows,etc.Singleblockmodulecontroldrive12(maximumcontrolandblock),16X48matrix8X8matrix(or32X48matrix),isasingleblockofMAX7219(orPS7219,HD7279,ZLG72898279andothersimilarLEDdisplaydrivermodule)12times(or24times)!Canusecascademeansanybitmapbigscreencomposed.Showgoodeffect,lowconsumption,andthecostofusingMAX7219circuitislower.TheLEDdisplayinspectionmethod,Seeappearance,specifications,screenbodyflatness,screentheattachmentwithin2lookbad,afterthelightscreenisnotinscope,thescreen(generallynowbasicallyno)Colorconsistency,displaystextdisplayisnormal,thepicturetoscreen,full-colorplaywhite,red,greenandblue.TechnicaladvantageExistingcommonindoorfull-colorschemecomparison:1thematrixmodules:design,colordotmatrixLCDbyindoorartifactsAdvantage:thecostofrawmaterials,productionandprocessingofthemostadvantageofsimpleprocess,qualityisstable.Faults:colorconsistency,Mosaicphenomenon,seriouseffect.2.Singlelampschemesforsolvingthebitmapscreencolor:foroutdoorscreentechnology,aschemeofpixels,outdoormultiplexingtechnique(alsocalledpixelsharingtechnology,virtualpixelstoindoordisplaytechnology)transplantation.Advantage:colorconsistencythanbitmapmoduleofgoodway.Weakness:theeffectnotbeautiful,colormixing,horizontalAngleandhaveoffcolor.Processisrelativelycomplex,anti-statichigh.Actualpixelresolutiondo10,000moredifficult.FeaturesCompatiblewithMCS-51Products8KBytesofIn-SystemProgrammable(ISP)FlashMemory1000Write/EraseCyclesFullyStaticOperation:0Hzto33MHzThree-levelProgramMemoryLock第4页256x8-bitInternalRAM32ProgrammableI/OLinesThree16-bitTimer/CountersEightInterruptSourcesFullDuplexUARTSerialChannelLow-powerIdleandPower-downModesInterruptRecoveryfromPower-downModeWatchdogTimerDualDataPointerPower-offFlagDescriptionTheAT89C52isalow-power,high-performanceCMOS8-bitmicrocontrollerwith8Kbytesofin-systemprogrammableFlashmemory.ThedeviceismanufacturedusingAtmelshigh-densitynonvolatilememorytechnologyandiscompatiblewiththeindustrystandard80C51instructionsetandpinout.Theon-chipFlashallowstheprogrammemorytobereprogrammedin-systemorbyaconventionalnonvolatilememoryprogrammer.Bycombiningaversatile8-bitCPUwithinsystemprogrammableFlashonamonolithicchip,theAtmelAT89C52isapowerfulicrocontrollerwhichprovidesahighly-flexibleandcost-effectivesolutiontomanyembeddedcontrolapplications.TheAT89C52providesthefollowingtandardfeatures:8KbytesofFlash,256bytesofRAM,32I/Olines,Watchdogtimer,twodatapointers,three16-bittimer/counters,asix-vectortwo-levelinterruptarchitecture,afullduplexserialport,on-chiposcillator,andclockcircuitry.Inaddition,theAT89C52isdesignedwithstaticlogicforoperationdowntozerofrequencyandsupportstwosoftwareselectablepowersavingmodes.TheIdleModestopstheCPUwhileallowingtheRAM,timer/counters,serialport,andinterruptsystemtocontinuefunctioning.ThePower-downmodesavestheRAMcontentsbutfreezestheoscillator,disablingallotherchipfunctionsuntilthenextinterruptorhardwarereset.第5页中文翻译稿基于AT89C52的LED概述LED（LightEmittingDiode），发光二极管，是一种固态的半导体器件，它可以将电能转化为光能。LED的核心是一个半导体的晶片，晶片的负极附在一个支架上，另一端与电源连接的是正极，整个晶片用环氧树脂封装。半导体晶片由两个部分组成，一部分是P型半导体，在P型半导体中空穴占据了主要的地位，另一部分是N型半导体，其中主要是电子。当两者连接起来的时候，它们之间就形成了一个“P-N结”。当电流通过导线作用于这个晶片时，电子向P区迁移，随后电子在P区与空穴结合，这样就会以光子的形式发出能量，这便是LED的发光原理。而光的波长也就是光的颜色，是由P-N结的材料决定的。LED的历史，50年前人们就知道了半导体材料可以发光，且第一个商用二极管是在1960年诞生的。LED的英文是lightemittingdiode，其基本结构是一块电致发光的半导体材料，放在一个有引线的架子上，周围是用环氧树脂密封好的，这能起到保护内部芯线的作用，故LED的抗震性能比较好。最初LED被用在仪器仪表的指示灯中，后来各种颜色的LED在交通灯和大面积的显示屏中得到了广泛应用，拥有很好的经济和社会效益。以12英寸的红色交通灯为例，在美国，原来是将长寿命、低光效的140瓦白炽灯作为光源，它产生2000流明的白光。通过红色滤光片后，光损失了90%，只剩下200流明的红光。而在新设计的灯中，Lumileds公司采用了18个红色LED作为光源，包括电路损失在内，总共消耗14瓦电，便能产生相同的光效。LED光源在汽车信号灯中也有较重要的应用。对于照明而言，我们更需要白色的光源。发白光的LED灯是在1998年研发成功的。其是把GaN芯片和钇铝石榴石封装于一起制作而成的。GaN芯片发蓝光，用高温烧结制成的含Ce3+的YAG荧光粉受到蓝光的激发后发出黄色光，峰值为550nm。蓝光LED基片装在碗形反射腔中，覆盖以混有YAG的树脂薄层，约200-500nm。LED基片发出的蓝光会被荧光粉吸收，而另一部分的蓝光会与荧光粉发出的黄光混合，这样就能得到白光。现在，对于InGaN/YAG白色LED，可以通过改变YAG荧光粉的化学组成和调节荧光粉层的厚度，获得色温3500-10000K的各色白光。这种通过蓝光LED得到白光的方法，构造比较简单、成本也较低廉、技术成熟度高，所以被运用的最多。在上世纪60年代时，科学家通过半导体PN结的发光原理，研究出了LED发光二极管。当时研究的LED是用GaASP材料制成的，它的发光颜色是红色。经过了将近30年的发展，现在人们所熟知的LED可以发出红、橙、黄、绿、蓝等多种颜色的光。LED显示屏可以分为图文显示屏和视频显示屏，其都是由LED矩阵块所组成。图文显示屏能够和计算机同步显示出汉字、英文文本以及图形；视频显示屏采用的是微型计算机进行控制的，图文、图像并茂，可以实时、同步、清晰的播放各种信息，同时还可显示二维、三维动画、录像、电视、VCD节目以及现场实况。LED显示屏显示的画面色彩鲜艳，立体感强，静如油画，动如电影，被广泛应用于金融、税务、工商、邮电、体育、广告、厂矿企业、交通运输、教育系统、车站、码头、机场、商场、医院、宾馆、银行、证券市场、建筑市场、拍卖行、工业企业管理和其它公共场所。LED显示屏能够显示变化的数字、文字、图形图像；LED显示屏不仅能够用于室内环境还能够用于室外环境，它拥有投影仪、电视墙、液晶显示屏所无法比拟的优点。第6页LED显示屏的分类：1、按颜色基色分类单基色显示屏:单一颜色（比如：红色或绿色）。双基色显示屏：红和绿双基色，256级灰度、可以显示65536种颜色。全彩色显示屏：红、绿、蓝三基色，256级灰度的全彩色显示屏可以显示一千六百多万种颜色。2、按显示器件分类LED数码显示屏：显示器件为7段码数码管，适于制作时钟屏、利率屏等，显示数字的电子显示屏。LED点阵图文显示屏：显示器件是由许多均匀排列的发光二极管组成的点阵显示模块，适于播放文字、图像信息。LED视频显示屏：显示器件是由许多发光二极管组成，可以显示视频、动画等各种视频文件。3、按使用场合分类室内显示屏：发光点较小，一般3mm-8mm，显示面积一般几至十几平方米。室外显示屏：面积一般几十平方米至几百平方米，亮度高，可在阳光下工作，具有防风、防雨、防水功能。4、按发光点直径分类室内屏：3mm、3.75mm、5mm。室外屏：10mm、12mm、16mm、19mm、20mm、21mm、22mm、26mm。室外屏发光的基本单元为发光筒，发光筒的原理是将一组红、绿、蓝发光二极管封在一个塑料筒内共同发。5.显示方式