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1、ControllingvalveElectronicsisthestudyoftheflowofchargethroughvariousmaterialsanddevicessuchassemiconductors,resistors,inductors,capacitors,nano-structuresandvacuumtubes.Althoughconsideredtobeatheoreticalbranchofphysics,thedesignandconstructionofelectroniccircuitstosolvepracticalproblemsisanes
2、sentialtechniqueinthefieldsofelectronicengineeringandcomputerengineering.Thissciencestartsabout1908withtheinventionbyDrLeeDeForestofthevalve(triode)Before1950thissciencewasnamed"Radio"or"Radiotechnics"becausethatwasitsprincipalapplication.Thestudyofnewsemiconductordevicesandsurroundingtechnol
3、ogyissometimesconsideredabranchofphysics.Thisarticlefocusesonengineeringaspectsofelectronics.Electronicsystemsareusedtoperformawidevarietyoftasks.Themainusesofelectroniccircuitsare:TheControllingvalveandprocessingofdata.Theconversionto/fromanddistributionofelectricpower.Boththeseapplicationsi
4、nvolvethecreationand/ordetectionofelectromagneticfieldsandelectriccurrents.Whileelectricalenergyhadbeenusedforsometimepriortothelate19thcenturytotransmitdataovertelegraphand7telephonelines,developmentinelectronicsgrewexponentiallyaftertheadventofradio.Onewayoflookingatanelectronicsystemistodi
5、videitinto3parts:Inputs–Electronicormechanicalsensors(ortransducers).Thesedevicestakesignals/informationfromexternalsourcesinthephysicalworld(suchasantennasortechnologynetworks)andconvertthosesignals/informationintocurrent/voltageordigital(high/low)signalswithinthesystem.Signalprocessors–Thes
6、ecircuitsservetomanipulate,interpretandtransforminputtedsignalsinordertomakethemusefulforadesiredapplication.Recently,complexsignalprocessinghasbeenaccomplishedwiththeuseofDigitalSignalProcessors.Outputs–Actuatorsorotherdevices(suchastransducers)thattransformcurrent/voltagesignalsbackintousef
7、ulphysicalform(e.g.,byaccomplishingaphysicaltasksuchasrotatinganelectricmotor).Forexample,atelevisionsetcontainsthese3parts.Thetelevision'sinputtransformsabroadcastsignal(receivedbyanantennaorfedinthroughacable)intoacurrent/voltagesignalthatc
