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1、Chapter1ElectricandElectronicTechnologyFundamentalsUnit3TransistorTextNewWordsandExpressionsExercisesEndProcessofTranslationUnit3TransistorAtransistorisasemiconductordeviceusedtoamplifyandswitchelectronicsignals.Itismadeofasolidpieceofsemiconductormaterial,withatleastthree
2、terminalsforconnectiontoanexternalcircuit.Avoltageorcurrentappliedtoonepairofthetransistor'sterminalschangesthecurrentflowingthroughanotherpairofterminals.Becausethecontrolled(output)powercanbemuchmorethanthecontrolling(input)power,thetransistorprovidesamplificationofasign
3、al.Today,sometransistorsarepackagedindividually,butmanymorearefoundembeddedinintegratedcircuits.Thetransistoristhefundamentalbuildingblockofmodernelectronicdevices,andisubiquitousinmodernelectronicsystems.Followingitsreleaseintheearly1950sthetransistorrevolutionisedthefiel
4、dofelectronics,andpavedthewayforsmallerandcheaperradios,calculators,andcomputers,amongstotherthings.Unit3TransistorImportanceThetransistoristhekeyactivecomponentinpracticallyallmodernelectronics,andisconsideredbymanytobeoneofthegreatestinventionsofthetwentiethcentury.Itsim
5、portanceintoday'ssocietyrestsonitsabilitytobemassproducedusingahighlyautomatedprocess(semiconductordevicefabrication)thatachievesastonishinglylowper-transistorcosts.Unit3TransistorUnit3TransistorAlthoughseveralcompanieseachproduceoverabillionindividuallypackaged(knownasdis
6、crete)transistorseveryyear,thevastmajorityoftransistorsnowproducedareinintegratedcircuits(oftenshortenedtoIC,microchipsorsimplychips),alongwithdiodes,resistors,capacitorsandotherelectroniccomponents,toproducecompleteelectroniccircuits.Alogicgateconsistsofuptoabouttwentytra
7、nsistorswhereasanadvancedmicroprocessor,asof2009,canuseasmanyas2.3billiontransistors(MOSFETs)."About60milliontransistorswerebuiltthisyear[2002]...for[each]man,woman,andchildonEarth."Thetransistor'slowcost,flexibility,andreliabilityhavemadeitaubiquitousdevice.Transistorized
8、mechatroniccircuitshavereplacedelectromechanicaldevicesincontrollingappliancesandmachiner
