自動化專業(yè)英語(習題參考解答)

自動化專業(yè)英語姜書艷主編張昌華徐心皓何芳編著習題參考解答Unit1A.BasiclawsofElectricalNetworks[EX.1]Comprehension1.KCL:Thealgebraicsumofthecurrentsenteringanynodeiszero.KVL:Thealgebraicsumofthevoltagearoundanyclosedpathiszero.2.Node:Apointatwhichtwoormoreelementshaveacommonconnectioniscalledanode.Branches:asinglepathinanetworkcomposedofonesimpleelementandthenodeateachendofthatelement.Path:Ifnonodewasencounteredmorethanonce,thenthesetofnodesandelementsthatwehavepassedthroughisdefinedasapath.Loop:Ifthenodeatwhichwestartedisthesameasthenodeonwhichweended,thenthepathis,bydefinition,aclosedpathoraloop.apathisaparticularcollectionofbranches.3.4,5,Wecanformapathbutnotaloop.4.vR2=32V,Vx=6V[EX.2]TranslationfromEnglishtoChinese1.如果定義具有最大連接支路數(shù)的節(jié)點為參考節(jié)點，那么得到的方程相對來說比較簡單。2.我們發(fā)現(xiàn)分析的主要步驟是得到含有一個未知變量的方程，該未知變量是該節(jié)點對兩端的電壓。3.然而，這個電阻相對于電路中其他的電阻來說是如此的小以至于我們可以在不引起明顯誤差的情況下忽略它的存在。4.與其他方式相比,下面這種方式在列方程時不容易犯錯誤.在頭腦中按順時針方向沿閉合路徑走一遍,如果首先遇到的是元件標有"+"號的端子,就直接寫下它的電壓;如果首先遇到的是標有"-"的端子,則寫下該電壓的負值。5.正確分析電路的關(guān)鍵是先要在電路中規(guī)范地標出所有電壓和電流。6.仔細寫出KCL和KVL方程就可以得到正確的關(guān)系式，必要的時候，比如未知量多余最初得到的方程數(shù)時再應(yīng)用歐姆定律。7.節(jié)點分析法基于基爾霍夫電流定律，運用節(jié)點分析法可以對不同的電路建立方程。8.注意，為了保持一致性，式中把所有的電流源（定義為流入節(jié)點1）放在了方程左邊，把所有經(jīng)過電阻流出節(jié)點1的電流放到了方程右邊。9.在一個電路中，通過電阻的電壓（稱為壓降），總有與電源極性相反的情況。10.因為電子流過一個電阻時會失去能量，因此它們會以較低的能級出現(xiàn)。[EX.3]TranslationfromChinesetoEnglish1.Itshouldbeemphasizedthatthevoltagecannotbedefinedinasinglepoint-itisdefinedasthepotentialdifferencebetweentwopoints.2.Notallofthegroundsaretheground;thisfactwillcausealotofsafetyissuesandelectricalnoise.3.Butasthesecorrosivepipesareplacedbylower-cost,moremodernandmorenon-conductivePVCpipingsystem,thelowimpedancepathtothegroundwillnotexistanymore.4.Kirchhoff'scurrentlawisbasedontheprincipleofconservationofcharge,andKirchhoff'svoltagelawisbasedonenergyconservationprinciple.Theyareboththebasiclawsofphysics.5.Ifthepublicportofthecircuitisnotconnectedwiththegroundthroughsomelow-impedancepath,itmayleadtosomepotentialdangers.6.Sincethesamecurrentflowsthrougheachresistor,thevoltagedropsareproportionaltotheOhmicvaluesoftheresistor.7.Ifallthevoltagedropsaroundaclosedloopareaddedandthenthistotalissubtractedfromthesourcevoltage,theresultiszero.8.Whentheresistorvoltagesareaddedtogether,theirsumwillequalthesourcevoltage.Anynumberofresistorscanbeadded.9.YoucanverifyKCLbyconnectingacircuitandmeasuringeachbranchcurrentandthetotalcurrentfromthesource.10.Additionalresistorsconnectedinparallelwillfurtherreducetheresistanceandincreasethetotalcurrent.[EX.4]Filloutthespaceaftertherecord.Inanodal1thevariablesinthecircuitareselectedtobethenodevoltage.Thenodevoltagesaredefinedwithrespecttoa2pointinthecircuit.Onenodeisselectedasthe3node,andallothernodevoltagesare4withrespecttothatnode.Quiteoftenthisnodeistheonetowhichthelargestnumberof5areconnected.Itiscommonlycalled6becauseitissaidtobeatground-zero7,anditsometimesrepresentsthechassisorgroundlineinan8circuit.Wewillselectourvariablesasbeing9withrespecttothereferencenode.Ifoneormoreofthenodevoltagesareactuallynegativewithrespecttothereferencenode,mon3.reference4.defined5.branches6.ground7.potential8.practical9.positive10.indicateB.TheCharacteristicsofBasicElements[EX.1]Comprehension1.Theinherentresistivityofamaterialandthedevicegeometrygovernedtheresistance.2.Activeelementiscapableoffurnishinganaveragepowergreaterthanzerotosomeexternaldevice,butpassiveelementcannotsupplyanaveragepowerthatisgreaterthanzerooveraninfinitetimeinterval.[EX.2]TranslationfromEnglishtoChinese1.沒有電子流過電容器的電介質(zhì)，因為它是絕緣體。2.在電路中所使用的電容值大多數(shù)都是在微法（μF的）和皮法（pF）量級的。3.在任何絕緣的電容中都會有很小的電流流過，因此，電容上充的電最終都將流失。4.當有電流流過一個電感時，就會產(chǎn)生磁場。當電流值的改變，該磁場值也會隨之改變。5.自感應(yīng)是一種因線圈中的電流變化而引起產(chǎn)生感應(yīng)電壓能力的度量。6.當兩個導(dǎo)體并排放置，它們之中總會產(chǎn)生一定的電容7.電容和電感都是無源元件，只能儲存和釋放有限的能量。8.任何實際元件都有一定的固有電阻、電容和電感，盡管在實際中它們可能很小。9.我們需要記住的是，任何不互相接觸的兩個導(dǎo)電表面之間均存在非零的電容（盡管可能很?。?。10.電感兩端的電壓為零時仍然可以儲存能量，例如當流過它的電流為恒定值時。[EX.3]TranslationfromChinesetoEnglish1.Rangeofcapacitorsandinductorscanbeverylarge,sosometimesitdeterminesthecircuitperformance,andsometimestheinfluenceisquitesmall.Withhigherandhigherworkingfrequencyofcomputerandcommunicationsystemsandagrowingnumberofintegratedcomponents,thisfeaturecannotbeignored.2.Letusvisualizesomeexternaldeviceconnectedtothiscapacitorandcausingapositivecurrenttoflowintooneplateofthecapacitorandoutoftheotherplate.3.Thepositivecurrententeringoneplaterepresentspositivechargemovingtowardthatplatethroughitsterminallead;thischargecannotpassthroughtheinteriorofthecapacitor,anditthereforeaccumulatesontheplate.4.Eachcapacitorvoltageandeachinductorcurrentmustremainconstantduringtheswitchinginterval.5.Afiniteamountofenergycanbestoredinacapacitorevenifthecurrentthroughthecapacitoriszero,suchaswhenthevoltageacrossitisconstant.6.Whenweusetheprincipleofsuperposition,wemustregardtheinitialelectricvoltageandtheinitialinductorcurrentasindependentsources,andeachinitialvaluemustberemovedattheappropriatetime.7.Acapacitorconsistsoftwoconductingsurfacesonwhichchargemaybestored,separatedbyathininsulatinglayerthathasaverylargeresistance.8.Capacitorsinseriescombineasdoconductancesinseries,orresistorsinparallel.9.Theinductorwhichisequivalenttoseveralinductorsconnectedinseriesisonewhoseinductanceisthesumoftheinductancesintheoriginalcircuit.Thisisexactlythesameresultweobtainedforresistorsinseries.10.Thepresenceofalargevoltageacrossashortdistanceequatestoaverylargeelectricfield;thestoredenergyisdissipatedinionizingtheairinthepathofthearc.[EX.4]Filloutthespaceaftertherecord.Aninductorisbasicallya1ofwire.Thematerialaroundwhichthecoilisformediscalledthecore.Coilsarewoundoneither2ormagneticmaterials.Examplesofnonmagnetic3areair,wood,copper,plastic,andglass.Thepermeabilitiesofthesematerialsarethesameasfora4.Examplesofmagneticmaterialsareiron,5,steel,cobalt,oralloys.Thesematerialshavepermeabilitiesthatare6orthousandsoftimesgreaterthanthatofavacuumandare7asferromagnetic.Avides9.path10.fieldUnit2A.DigitalCircuits[EX.2]TranslationfromEnglishtoChinese1.同樣，極少數(shù)因為熱運動而產(chǎn)生的少數(shù)載流子穿過結(jié)亦形成電流，但這些電流在一個正向偏置二極管的總電流當中微不足道，因此也沒有畫出。2.當集電極-發(fā)射極電壓維持很小時，晶體管中歐姆必電阻（尤其是輕摻雜的集電極）變得很重要。3.多數(shù)情況下兩個區(qū)是等同的，可以對器件不做任何修改就進行互換，它們是對稱的。4.這種情況一旦發(fā)生，不管漏-源電壓是多少，都沒有任何電流能通過晶體管，晶體管被稱為截止。5.溝道兩端的電壓降不會隨著漏極電壓的增加而無限增加，實際上夾斷區(qū)會變寬，因此漏極電流會達到上限。6.我們還發(fā)現(xiàn)，MOSFET電路在低頻率時輸入阻抗的基本上是無限的，這意味著零輸入偏置電流。7.增強型MOSFET實際上有一個溝道，使得只有當電源給門上加了合適的偏置，才有電流流過。8.我們可以把它想象成一個N型半導(dǎo)體，其中有適量的電子作為載流子，然后在它的一邊放上一塊P型半導(dǎo)體。9.因為NPN型晶體管中有兩個PN結(jié)，所以這種晶體管由兩個內(nèi)在陽極連接在一起的二極管組成。10.一種非常有用且簡單的測試雙擊晶體管好壞的方法是，用歐姆表連接晶體管的任意兩端并觀察電阻值。[EX.3]TranslationfromChinesetoEnglish1.Thejunctiondiode,thebipolarjunctiontransistor,andtheMOStransistorarethethreemostimportantsemiconductordevices.Togetherwithresistorsandcapacitors,theyformthevastmajorityoftheelementsusedinmodernintegratedcircuits.2.MOStransistorsarenormallyconsideredmajoritycarrierdevices,whichconductonlyafterachannelforms.3.Inthesaturationregion,thecollector-emittervoltageremainssosmallthatthecollector-basejunctionisslightlyforward-biased.4.Acollectorcurrent100timeslargerthanthebasecurrentflowsacrossthebase-collectorjunctioneventhoughthisjunctionremainsreversebiased.5.Moreandmoremajoritycarriersmakethetransitacrossthedepletionregionwithoutbeingsweptbackbytheelectricfield.6.Theelectricalcharacteristicsofthetransistorcanberepresentedontwographs,consideredtheinputcharacteristicandtheoutputcharacteristic.7.Abadtransistoroftenexhibitsalowresistanceinbothsenses(ashortedjunction)orahighresistanceinbothsenses(anopenjunction).8.AP-typesemiconductorhasholesthatbehavelikepluschargesasthemajoritychargecarrier.9.Inthesetransistors,conductionoccursinachannelformedinn-typebulkmaterialviapositivechargecarriers.10.NoticethatthecurrentIDisplottedversusthedrain-sourcevoltageVDSacrossthedevice.[EX.4]Filloutthespaceaftertherecord.Whenadrain-sourcevoltageincreasesfurther,however,somethingrathersurprisinghappens:the1currentlevelsoffandremainsvirtuallyconstantwithincreasingVDS.Thereasonisavoltagedrop(IRdrop)alongthe2N-channelmaterial.Ifthegateisatground3(relativetosource)andthe4regionnearthetopofthebarisatavoltageVDS,thegateis5relativetothechannelbyaboutthisvoltage.Thus,thegate-channeldiode6isreversebiasedbytheamountVDS,andalargedepletionzoneis7thattendstopinchoffthechannel.However,thecurrentdoesnotstopbecausetheIR8wouldthenvanishandthechannelwouldopenagain;instead,a9channelformsthatbecomeslongerwithincreasedVDSduced8.drop9.narrow10.flowB.TheIntroductionofVHDL[EX.2]TranslationfromEnglishtoChinese1.穩(wěn)定時間，建立繼電器連接并使電路穩(wěn)定所需的時間。2.提出二階有源濾波器的一種設(shè)計方法，給出三種濾波器電路，分析了每種電路的特點。3.要獲得脈沖反應(yīng)或階躍反應(yīng)的精確解，最好的辦法是用數(shù)字或模擬計算機求解原始微分方程。4.實驗結(jié)果表明并聯(lián)系統(tǒng)具有動態(tài)響應(yīng)快速，均流性能好的特點。5.在任一瞬間，沿著電路的任一（有向）回路繞行，正向電壓（具有正極性的電壓）之和等于反向電壓（具有負極性的電壓）之和。6.隨著時間的推移，所有實際的電容，即使沒有接到電路中去，最終都將完全放電。7.假定初始能量可能同時存在于電感和電容中，換句話說，電感電流和電容電壓的初始值可能同時為非零值。8.求解初始值總是從分析不連續(xù)性出現(xiàn)之前各儲能元件的狀態(tài)開始。9.理想電阻可以代替實際RC或RLC電路具有的實際電阻。10.假定電路已處于現(xiàn)有狀態(tài)很長的時間，并且所有的電流和電壓均為常量。[EX.3]TranslationfromChinesetoEnglish1.Nodefectshavebeenfoundinthesecircuits.2.Astepresponseisgeneratedwhentheprosthetichandtouchesanobject.3.Theoutputwillpassthroughatransientphaseandsettledowntoasteady-stateresponsethatwillbeofthesameformas,orboundedby,theinput.4.Thenthenodalequationsbasedonthenodalcurrentdifferential(equilibrium)relationshipareobtainedaccordingtoKCL.5.ForthepurposeofapplyingKVL,apathhasanorientationinthesensethatin“walking”alongthepathonewouldenteroneofthenodeandexittheother.6.FortheremainderofourdiscussionsconcerningRLCcircuits,wewillalwaysrequiretwoinitialconditionsinordertocompletelyspecifytheresponse.7.Thecompleteresponseofasecond-ordersystemconsistsofaforcedresponseandanaturalresponse.8.Iftherearenoneactinginthecircuitaftertheswitchingordiscontinuityiscompleted,thenthecircuitissource-freeandthenaturalresponseaccountsforthecompleteresponse.9.IfthevalueoftheresistanceinaparallelRLCcircuitbecomesinfinite,orzerointhecaseofaseriesRLCcircuit,wehaveasimpleLCloopinwhichanoscillatoryresponsecanbemaintainedforever.10.DuringthetransientresponseofanRLCcircuit,energyistransferredbetweenenergystorageelementstotheextentallowedbytheresistivecomponentsofthecircuit,whichactstodissipatetheenergyinitiallystored.[EX.4]Filloutthespaceaftertherecord.WenowconsiderthoseRLCcircuitsinwhichDCsourcesare1intothenetworkandproduceforced2thatdonotnecessarilyvanishastimebecomesinfinite.Thegeneralsolutionisobtainedbythesame3thatwasfollowedinRLandRCcircuits:theforcedresponseis4completely;thenaturalresponseisobtainedasasuitable5formcontainingtheappropriatenumberof6constants;the7responseiswrittenasthesumoftheforcedandthenaturalresponses;andthe8conditionsarethendeterminedand9tothecompleteresponsetofindthevaluesoftheconstants.Iplete8.initial9.applied10.frequentlyUnit3A.DigitalCircuits[EX.2]TranslatethefollowingpassagesintoChinese.1.通常，稱邏輯值0或1為二進制數(shù)字或位。2.邏輯電路可簡單地表示為具有一定輸入輸出端數(shù)目的“黑匣子”。3.能夠用來構(gòu)建任何組合數(shù)字邏輯電路的，只有3種基本邏輯函數(shù)，即“與”，“或”和“非”。4.在討論電子邏輯電路的時候，數(shù)字設(shè)計師通常用“低”和“高”分別代替0和1。5.“與非”門的輸出和與門的輸出反相。6.“或非”門的輸出與或門的輸出反相。7.組合邏輯電路的運算可由真值表完全描述，真值表列出了輸入和對應(yīng)輸出的各種組合。8.時序邏輯電路的特性可由狀態(tài)表來描述，狀態(tài)表列出了電路的輸出和下一狀態(tài)。9.邏輯系列是一些不同的集成電路芯片的集合。10.目前，HDL是描述PLD，CPLD，F(xiàn)PGA或ASIC的頂級和詳細模塊級設(shè)計的迄今最普遍使用的方法。[EX.3]TranslatethefollowingpassagesintoEnglish.1.A2-inputANDgate,producesa1outputifbothofitsinputsare1;otherwiseitproduces0output.2.ANOTgate,morecommonlycalledaninverter,producesanoutputvaluethatistheoppositeoftheinputvalue.3.A2-inputORgateproducesa1outputifoneorbothofitsinputsare1,itproducesa0outputonlyifbothinputsare0.4.Intheschematicdiagramforadigitalcircuit,pindiagramsarenotused.Instead,thevariousgatesaregroupedfunctionally.5.AlthoughSSIICsarestillsometimesusedas“glue”totietogetherlarger-scaleelementsincomplexsystems,theyhavebeenlargelysupplantedbyprogrammablelogicdevices(PLDs).6.AtthesametimethatCPLDswerebeinginvented,otherICmanufacturerstookadifferentapproachtoscalingthesizeofprogrammablelogicchips.7.TheeaseofprototypingandmodifyingPLD-andFPGA-basedsystemscaneliminatetheneedforsimulationinboard-leveldesign.8.ThelowestlevelofdigitaldesignisdevicephysicsandICmanufacturingprocesses.9.AnICisnormallymountedonaprinted-circuitboard(PCB).10.ThenumberoftransistorspersquareinchinthenewestICswilldoubleeveryyear.[EX.4]Filloutthespaceaftertherecord.As1circuittechnologyadvances,oneemphasisisonincreasedcircuit2.Themaximumnumberofcircuit3perunitareaisdeterminedeitherbypowerdissipationdensityorbytheareaoccupiedbytransistorsandrelated4.OneformofNMOScircuitlogicthatminimizes5dissipationandmaximizesdevicedensityiscalledpass6logic.Passtransistorcircuitsuseminimum-sizedtransistors,providinghighdensityandhighoperatingspeed.TworkB.TheIntroductionofVHDL[EX.2]TranslatethefollowingpassagesintoChinese.1.實體的內(nèi)部操作由結(jié)構(gòu)體定義去說明。2.實體的端口及其模式和類型都能被調(diào)用它的模塊所看見。3.典型VHDL程序中常用的類型是用戶定義類型。4.VHDL將數(shù)組定義為同類型元素的有序集合，每個元素由數(shù)組下標來選擇。5.函數(shù)調(diào)用時，調(diào)用函數(shù)用實際參數(shù)代替形式參數(shù)。6.函數(shù)可以定義它自己的局部類型、常量、變量、嵌套函數(shù)和過程。7.VHDL的過程與函數(shù)相似，但是它不返回結(jié)果。8.VHDL包是一個文件，它包括可用于其他程序中的對象定義。9.在VHDL中，同一個結(jié)構(gòu)體的并發(fā)語句是同時執(zhí)行的。10.使用組件的VHDL結(jié)構(gòu)體通常稱為結(jié)構(gòu)描述或結(jié)構(gòu)設(shè)計。[EX.3]TranslatethefollowingpassagesintoEnglish.1.VHDLdefinesmanyspecialcharacterstrings,calledreservedwordsorkeywords.2.VHDLvariablesaresimilartosignals,exceptthattheyusuallydon’thavephysicalsignificanceinacircuit.3.Theentity-nameinthisdefinitionmustbethesameastheonegivenpreviouslyintheentitydeclaration.4.Anarchitecture’sexternalinterfacesignals(ports)areinheritedfromtheport-declarationpartofitscorrespondingentitydeclaration.5.Everysignal,variable,andconstantinaVHDLprogrammusthaveanassociated“type.”6.Likeafunctioninahigh-levelprogramminglanguage,aVHDLfunctionacceptsanumberofargumentsandreturnsaresult.7.EachoftheargumentsandtheresultinaVHDLfunctiondefinitionorfunctioncallhasapredeterminedtype.8.VHDL’skeybehaviorelementisthe“process.”9.TheinputstotheUUTarecreatedwithinthebestbench,andtheoutputsareobservedonthesimulator.10.TheUUTisinstantiatedusinglocalsignalsforitsinputsandoutputs.[EX.4]Filloutthespaceaftertherecord.UnlikeC,VHDLisastronglytypedlanguage.Thismeansthatthe1doesnotallowyouto2avaluetoasignalorvariableunlessthetypeofthevalueprecisely3Strongtypingisbothablessingandacurse.Itmakesyour4morereliableandeasierto5,becauseitmakesitdifficultforyoutomake“dumb6”whereyouassignavalueofthewrongtypeorsize.Ontheotherhand,itcanbeexasperatingattimes.Evensimple7,suchasreinterpretinga2-bit8asaninteger(forexample,to9oneoffouroutcomesina“case”101.gram5.debug6.errors7.operations8.signal9.select10.statementUnit4A：OperationalAmplifiers[EX.2]TranslatethefollowingpassagesintoChinese.一般帶有非常高的電壓增益、非常高的輸入電阻、非常低的輸出電阻這些特性的放大器通常稱為運放。在原理圖中，當電源電壓在某處標明時，通常可將運放的原理圖符號中的電源端省略。運算放大器可以用一個電壓值由反相和非反相輸入兩端的電壓值所決定的理想電壓源加上有限輸入輸出阻抗效應(yīng)來表示。差分輸出運放的簡化模型只在某些特殊反饋條件下是一種精確近似。理想運放的輸出阻抗通常認為為零。這樣它就可以為其驅(qū)動的負載提供任意大的電流。當反相與非反相輸入端之間出現(xiàn)零信號時，放大器輸出為零。理想運放特性的一個重要副產(chǎn)品為其求和點（即反相輸入端）不會引導(dǎo)任何電流流入放大器。理想運放的增益可認為是無窮大，因此它可以將輸入電壓驅(qū)動到任意值以滿足輸入條件。理想運放可以驅(qū)動任意負載而不產(chǎn)生輸出阻抗壓降。加在運放輸入端的電子信號并不是瞬間反映在運放的輸出端上；在輸入和輸出之間有一段有限的傳播時間。[EX.3]TranslatethefollowingpassagesintoEnglish.AnamplifierisaDC-coupleddevicewithdifferentialinputsandasingleoutput.Ainfinitesmallinputsignalmaybeamplifiedtoaverylargesignalduetoinfinitevoltagegain.Therearetwobasicconfigurationsofopamps:theinvertingconfigurationandthenon-invertingconfiguration.Typicallytheoutputoftheop-ampiscontrolledby\o"Negativefeedback"negativefeedbackor\o"Positivefeedback"positivefeedback.Highinput\o"Electricalimpedance"impedanceattheinputterminalsandlowoutputimpedanceareimportanttypicalcharacteristicsofop-amps.ManystandardICop-ampscostonlyafewcentsinmoderateproductionvolume;howeversomeintegratedorhybridoperationalamplifierswithspecialperformancespecificationsmaycostover$100USinsmallquantities.Moderndesignsareelectronicallymoreruggedthanearlierimplementationsandsomecansustaindirect\o"Short-circuit"shortcircuitsontheiroutputswithoutdamage.Operationalamplifiersareusuallyusedwithfeedbackloopswheretheoutputoftheamplifierwouldinfluenceoneofitsinputs.Initsmostcommonuse,theop-amp'soutputvoltageiscontrolledbyfeedingafractionoftheoutputsignalbacktotheinvertinginput,whichprovides\o"Negativefeedback"negativefeedbacktotheamplifier[EX.4]Fillinthespacesaftertherecord.Amplifieraredevicesthatproduce1inputsignals.The2istheamplificationratiooftheoutputsignaltoitsinputsignals.Operationalamplifiersareoftencalled3,theyusuallyhave4inputs.Anop-amphas5inputimpedanceand6outputimpedance.Anidealop-amphas7inputimpedanceand8outputimpedance.Inanidealop-amp,wecouldassumethatno9flowsintotheinput.Op-ampsareoftenusedwith10feedback.magnified2.gain3.op-amp4.differential5.high6.low7.infinite8.zero9.current10.negativeB：TheApplicationofOperationalAmplifiers[EX.2]TranslatethefollowingpassagesintoChinese.運放可用于將一個電路與其它電路分隔或解耦。多個運放電路可以級聯(lián)起來以在避免顯著衰減的情況下修改輸入信號。非反相運放又稱帶增益的電壓跟隨器，或簡稱電壓跟隨器。反相運放又稱反相器。差分輸入放大器又稱差分放大器或減法器。當所選運放為電流反饋型時，反饋電阻就尤為重要。單位增益電路作為電子緩沖器用以電路或器件之間的隔離并防止不利的反應(yīng)。將現(xiàn)代的差分輸入放大器的非反相輸入端接地并在反相輸入端加上輸入電壓，即可當作反向放大器使用。將電容作為反向放大器的反饋元件，就得到了積分器。在實際中，積分器通常帶有一個功能開關(guān)。開關(guān)撥至“積分”模式時作為積分器工作，撥至“復(fù)位”模式時其對電容放電并作為反相器工作。[EX.3]TranslatethefollowingpassagesintoEnglish.syednayfsomlsnvoltageandcurrentsignals.Inclose-loopconfiguration,thevoltageattheinvertinginputisalwaysdriventothesamepotentialasthenon-invertinginput.Becausedifferentialinputamplifieronlyamplifiesthediferentialportionoftheinputsignal,itrejectsthecommon-modeportionoftheinputsignal..Fillinthespacesaftertherecord.Op-ampsareoftenusedwith1loops.Anegativefeedbackisonethatfeedsafractionof2signalbacktothe3input.Inanon-invertingop-amp,theinputsignalisconnectedtothe4input.Whentheresistorbetweenthenon-invertinginputandoutputiszero,theop-ampbecomesavoltage5.6feedbackdoesn’trequireadifferentialinput,thusisusedquiteoften.Aninverterhasits7inputconnectedtotheground.Anadderhasmoreinputconnectedtoits8input.Inanadder,currentinthefeedbackloopisthealgebraic9ofthecurrentduetoeachinput.Whentheoutputsignalisconnectedtothenon-invertinginput,it’scalled10feedback.UNIT5A：ComputerArchitectureandFunctions[EX.2]TranslatethefollowingsentencesintoChinese.1.程序設(shè)計語言使得程序能夠獨立于開發(fā)它的計算機，因為編譯器和匯編器可以將高級語言程序翻譯為任何機器的二進制指令。2.計算機的五個經(jīng)典組成部分是輸入、輸出、存儲器、數(shù)據(jù)通路以及控制器，后兩個我們有時候合稱為處理器。3.有些設(shè)備，例如網(wǎng)絡(luò)和硬盤，既向計算機提供輸入也接受輸出。4.內(nèi)存不僅是計算機運行時存儲程序的地方，它還包含程序運行時所需的數(shù)據(jù)。5.這些基本的指令集和操作系統(tǒng)提供給應(yīng)用程序員的接口合稱為應(yīng)用程序二進制接口（ABI）。6.總線是公共信號線的集合。7.計算機各部分通過地址總線、數(shù)據(jù)總線和控制總線互相連接。8.馮·諾依曼結(jié)構(gòu)不允許同時進行取指令和取數(shù)據(jù)，因而降低了運算速度。9.哈佛結(jié)構(gòu)常用于嵌入式系統(tǒng)處理中。10.哈佛結(jié)構(gòu)更高的執(zhí)行效率使得在哈佛結(jié)構(gòu)計算機上執(zhí)行同等復(fù)雜度的程序要比在馮·諾依曼結(jié)構(gòu)的計算機快。[EX.3]TranslatethefollowingsentencesintoEnglish.1.Thewordsofacomputer'slanguagearecalledinstructions.2.Floating-pointnumbersareusuallyamultipleofthesizeofaword.3.Computersareoftenshared,andaprocessormayworkonseveralprogramssimultaneously.4.Thebranchdatapathmustdotwooperations:computethebranchtargetaddressandcomparetheregistercontents.5.UnliketheMIPSarchitecturetheIA-32architecturecontainsinstructionsthatareverycomplexandcantaketensofcyclestoexecute.6.Inacomputer,instructionsanddataexistintheformofbinarydigits.7.Systemsoftwareincludesoperatingsystem,compilerandassembler,whichprovidesgeneralservices.8.Exampleofarchitectureattributesincludetheinstructionset,thenumberofbitsusedtorepresentvariousdatatypes,I/Omechanisms,andtechniquesforaddressingmemory.9.Thefunctionalbehaviorofthesystemconsistsoftheexchangeofdataandcontrolsignalsamongtheprocessor,memoryandI/Ocomponents.10.InVonNeumannarchitecture,dataandinstructionsarestoredinasingleread-writememory.[EX.4]Fillinthespacesaftertherecord.Acomputerunderstandsonlytwosignals1and2.Weusethenumbers3and4torepresentthem.Dataandinstructionsarerepresentedbyaseriesof0sand1s.Eachbinarydigitiscalleda5.PeopleusesimpleEnglishtorepresentbitsequences,makingupthe6language.Acomputerprocessorconsistsoftwomainunits,the7unitandthe8interfaceunit.A9isastoragedevicethateachcomputerhasforstoringdataandinstruction.In10architecture,dataandinstructionsarestoredseparately.1.on 2.off 3.0 4.1 5.bit 6.assembly 7.execution8.bus9.memory10.harvardB：EmbeddedSystems[EX.2]TranslatethefollowingpassagesintoChinese.1.嵌入式系統(tǒng)處理器和整個系統(tǒng)需有針對其所要實現(xiàn)的特定應(yīng)用的軟件。2.系統(tǒng)通過并行或串行I/O端口連接外部物理設(shè)備。3.嵌入式系統(tǒng)必需從開機后到關(guān)機前不停地執(zhí)行任務(wù)，甚至可能長期保持開機狀態(tài)。4.一般地，現(xiàn)實世界中的交互是通過傳感器和執(zhí)行器來完成的，而非標準PC上的鍵盤和屏幕。5.典型的嚴格時限特性是指對于某個特定交互的響應(yīng)必須在預(yù)定的時間內(nèi)發(fā)生。6.實時操作系統(tǒng)提供便于資源存取和共享的服務(wù)。7.對于消費電子領(lǐng)域的眾多產(chǎn)品，其代碼量每隔兩年翻一番。8.對可用軟硬件的重復(fù)利用是業(yè)界提倡的基于平臺的設(shè)計方法的核心。9.由于嵌入式系統(tǒng)硬件的海量復(fù)雜性，幾乎無法對所有類型的硬件器件做一個綜合的概括。10.嵌入式系統(tǒng)可能被運用在極端溫度、接近電磁輻射的主要源頭等條件下。[EX.3]TranslatethefollowingpassagesintoEnglish.1.Anmicroprocessorisusedwhenlargeembeddedsoftwareistobelocatedintheexternalmemorychips.2.Amicrocontrolleristhemostessentialcomponentofacontrolorcommunicationciucuit.3.Adigitalsignalprocessorisanessentialunitofanembeddedsystemforalargenumberofapplicationsneedingprocessingofsignals.4.Asystemthatisdesignedtomeetstricttimingrequirementsisoftenreferredtoasahardreal-timesystem.5.Embeddedsystemsarecontrolledbyamainprocessingcorethatistypicallyeithera\o"Microcontroller"microcontrollerora\o"Digitalsignalprocessor"digitalsignalprocessor.6.Hardwareforembeddedsystemsismuchlessstandardizedthanhardwareforpersonalcomputers.7.Atthechiplevel,embeddedchipsincludemicro-controllersandmicroprocessors.8.Embeddedprocessorshavetobeefficientandtheydonotneedtobeinstructionsetcompatiblewithcommonlyusedpersonalcomputers.9.Registersandarithmeticunitsofmanymodernarchitecturesare64bitswide.10.Computationaldemandsforembeddedsystemsareincreasing,especiallywhenmultimediaapplications,advancedcodingtechniquesorcryptographyareinvolved.[EX.4]Fillinthespacesaftertherecord.Embeddedsystemisa1versionofgeneralpurposecomputerforspecifiedtasks.2and3arethebasicbuildingblocksofanembeddedsystem.4istheheartofanembeddedsystem.Thehardwareofembeddedsystemalsoincludesessential5.Embeddedsystemhasstrongsupportof6multipletasks,strongprotectionfor7andverylowpower8.9systemand10systemaretwomajorembeddedoperatingsystems.Scalable2.Hardware3.Software4.Embeddedprocessor5.Peripherals6.Real-time7.Memory8.Consumption9.Real-time10.Time-sharingUNIT6A．