电子与通信技术专业英语 第6版 课件 6版 Project 4 Exercises

电子与通信技术专业英语电子信息工程学院Project4

TransistorVoltageAmplifierExercises1.WriteT(True)orF(False)besidethefollowingstatementsaboutthetext.a.Atransistorconsistsofthreelayersofsemiconductormaterial:athinlayerofonetypewiththeothertypeoneachside.b.Thecenterisbase,oneoutsidelayeristhecollector,andtheotheristheemitter.c.Currententerstheemitter,passesthroughthebase,andleavesviathecollector.d.Currentflowisalwayschangedirections.e.Ittakesagreatchangeofbasecurrenttocontrolarelativelylargecollectorcurrent.Itisthisabilitythatenablesthetransistortoamplify.f.Inthecommon-baseconnection,thesignalisintroducedintothecollector-basecircuitandextractedfromtheemitter-basecircuit.g.Inthecommon-emitterconnection,thesignalisintroducedintothebase-emittercircuitandextractedfromthecollector-emittercircuit.h.Thecommon-emitterconnectionhasmoremoderateinputandoutputimpedancethanthecommon-basecircuit.a.Therearetwopossiblearrangements:________inthemiddlewithp-typeoneachside(PNP)and________inthemiddlewithn-typeoneachside(NPN).

b.Becausetheinputoremitter-basecircuithasa_____impedanceintheorderof0.5to50ohms,andtheoutputor______________________hasahighimpedanceintheorderof1000ohmstoonemegohm,thevoltageorpowergaininthistypeofconfigurationmaybeintheorderof1500.2.Fillinthemissingwordsaccordingtothetext.c.Theinput(base-emitter)impedanceisintherangeof___to______ohms,andoutput(collector-emitter)impedanceisabout____to________ohms.Powergainsintheorderof10000(orabout40db)canberealizedwiththiscircuitbecauseitprovidesbothcurrentgainandvoltagegain.

d.Becausetheinputimpedanceofthetransistoris_____andtheoutputimpedance______inthisconnection,thevoltagegainislessthanoneandthepowergainisusuallylowerthanthatobtainedinacommon-baseoracommon-emittercircuit.2.Fill