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1、 TechnicalEnglish ForInformationScienceandElectronicEngineering Unit2 IntegratedCircuits PartI TheIntegratedCircuit 3 NewWords 4 NewWords 5 1 Digitallogicandelectroniccircuitsderivetheirfunctionalityfromelectronicswitchescalledtransistor Roughlyspeaking thetransistorcanbelikenedtoanelectronicallycon
2、trolledvalvewherebyenergyappliedtooneconnectionofthevalveenablesenergytoflowbetweentwootherconnections 1 由称为晶体管的电子开关得到它们的 各种 功能 粗略地说 晶体管好似一种电子控制阀 由此加在阀一端的能量可以使能量在另外两个连接端之间流动 6 1 Bycombiningmultipletransistors digitallogicbuildingblockssuchasANDgatesandflip flopsareformed Transistors inturn aremadefr
3、omsemiconductors Consultaperiodictableofelementsinacollegechemistrytextbook andyouwilllocatesemiconductorsasagroupofelementsseparatingthemetalsandnonmetals 2 查阅大学化学书中的元素周期表 你会查到半导体是介于金属与非金属之间的一类元素 7 1 Theyarecalledsemiconductorsbecauseoftheirabilitytobehaveasbothmetalsandnonmetals Asemiconductorcanb
4、emadetoconductelectricitylikeametalortoinsulateasanonmetaldoes Thesedifferingelectricalpropertiescanbeaccuratelycontrolledbymixingthesemiconductorwithsmallamountsofotherelements 可使半导体像金属那样导电 或者像非金属那样绝缘 8 1 Thismixingiscalleddoping Asemiconductorcanbedopedtocontainmoreelectrons N type orfewerelectron
5、s P type Examplesofcommonlyusedsemiconductorsaresiliconandgermanium PhosphorousandboronaretwoelementsthatareusedtodopeN typeandP typesilicon respectively 3 N型硅半导体掺入磷元素 而P型硅半导体掺入硼元素 9 2 Atransistorisconstructedbycreatingasandwichofdifferentlydopedsemiconductorlayers Thetwomostcommontypesoftransistors
6、 thebipolar junctiontransistor BJT andthefield effecttransistor FET areschematicallyillustratedinFigure2 1 图2 1给出了双极型晶体管和场效应晶体管的图示 10 2 Thisfigureshowsboththesiliconstructuresoftheseelementsandtheirgraphicalsymbolicrepresentationaswouldbeseeninacircuitdiagram TheBJTshownisanNPNtransistor becauseitis
7、composedofasandwichofN P Ndopedsilicon Whenasmallcurrentisinjectedintothebaseterminal alargercurrentisenabledtoflowfromthecollectortotheemitter 它们用于电路图中的符号 当小电流注入基极时 可使较大的电流从集电极流向发射极 11 2 TheFETshownisanN channelFET whichiscomposedoftwoN typeregionsseparatedbyaP typesubstrate Whenavoltageisappliedto
8、theinsulatedgateterminal acurrentisenabledtoflowfromthedraintothesource ItiscalledN channel becausethegatevoltageinducesanN channelwithinthesubstrate enablingcurrenttoflowbetweentheN regions 将电压加在绝缘的栅极上时 可使电流由漏极流向源极 因为栅极电压诱导基底上的N通道 使电流能在两个N区域之间流动 12 3 AnotherbasicsemiconductorstructureshowninFigure2
9、 1isadiode whichisformedsimplybyajunctionofN typeandP typesilicon Diodesactlikeone wayvalvesbyconductingcurrentonlyfromPtoN 二极管的作用就像一个单向阀门 由于电流只能从P流向N 13 3 Specialdiodescanbecreatedthatemitlightwhenavoltageisapplied Appropriatelyenough thesecomponentsarecalledlightemittingdiodes orLEDs Thesesmalllig
10、htsaremanufacturedbythemillionsandarefoundindiverseapplicationsfromtelephonestotrafficlights 这种小灯泡数以百万计地被制造出来 有各种各样的应用 从电话机到交通灯 14 4 Theresultingsmallchipofsemiconductormaterialonwhichatransistorordiodeisfabricatedcanbeencasedinasmallplasticpackageforprotectionagainstdamageandcontaminationfromtheout
11、 sideworld 4 半导体材料上制作晶体管或二极管所形成的小芯片用塑料封装以防损伤和被外界污染 15 4 Smallwiresareconnectedwithinthispackagebetweenthesemiconductorsandwichandpinsthatprotrudefromthepackagetomakeelectricalcontactwithotherpartsoftheintendedcircuit 从封装内伸出以便与 使用该晶体管的 电路其余部分连接 16 4 Onceyouhaveseveraldiscretetransistors digitallogicc
12、anbebuiltbydirectlywiringthesecomponentstogether Thecircuitwillfunction butanysubstantialamountofdigitallogicwillbeverybulky becauseseveraltransistorsarerequiredtoimplementeachofthevarioustypesoflogicgates 任何实质性的数字逻辑 电路 都将十分庞大 因为要在各种逻辑门中每实现一种都需要多个晶体管 17 5 Atthetimeoftheinventionofthetransistorin1947
13、byJohnBardeen WalterBrattain andWilliamShockley theonlywaytoassemblemultipletransistorsintoasinglecircuitwastobuyseparatediscretetransistorsandwirethemtogether In1959 JackKilbyandRobertNoyceindependentlyinventedameansoffabricatingmultipletransistorsonasingleslabofsemiconductormaterial 购买多个分离的晶体管 将它们
14、连在一起 一种将多个晶体管做在同一片半导体材料上的方法 18 5 Theirinventionwouldcometobeknownastheintegratedcircuit orIC whichisthefoundationofourmoderncomputerizedworld AnICissocalledbecauseitintegratesmultipletransistorsanddiodesontothesamesmallsemiconductorchip Insteadofhavingtosolderindividualwiresbetweendiscretecomponents
15、 anICcontainsmanysmallcomponentsthatarealreadywiredtogetherinthedesiredtopologytoformacircuit IC包含按照形成电路所要求的拓扑结构连在一起的许多小元件 而无需再将分立元件的导线焊接起来 19 6 AtypicalIC withoutitsplasticorceramicpackage isasquareorrectangularsilicondiemeasuringfrom2to15mmonanedge Dependingontheleveloftechnologyusedtomanufacturet
16、heIC theremaybeanywherefromadozentotensofmillionsofindividualtransistorsonthissmallchip 每一边2mm至15mm的方形或矩形硅片 在这种小片上可能有几十个到几百万个晶体管 20 6 Thisamazingdensityofelectroniccomponentsindicatesthatthetransistorsandthewiresthatconnectthemareextremelysmallinsize DimensionsonanICaremeasuredinunitsofmicrometers withonemicrometer 1mm beingonemillionthofameter Toserveasareferencepoint ahumanhairisroughly100mmindiameter SomemodernICscontaincomponentsandwiresthataremeasuredinincrementsassmallas0 1mm 1微米是1米的百万分之一
