Maincategories
Antiviruscomponents,electroniccomponents,pneumaticcomponents,Hallcomponents,flashcomponents,hydrauliccomponents,electricalcomponents,Excomponents.
Hall
Introduction
HallelementisasemiconductorthatusestheHalleffect.Itisgenerallyusedtodeterminetherotorspeedinamotor,suchasthemagneticDrums,coolingfansincomputers,etc.;isamagneticsensorbasedontheHalleffect,whichhasdevelopedintoadiversefamilyofmagneticsensorproductsandhasbeenwidelyused.
Fabricationmaterials
Hallelementscanbefabricatedwithavarietyofsemiconductormaterials,suchasGe,Si,InSb,GaAs,InAs,InAsP,andmultilayersemiconductorheterostructurequantumwellmaterials,etc..
Advantages
Halldeviceshavemanyadvantages,andtheirstructureisfirm.Smallsize,lightweight,longlife,easyinstallation,lowpowerconsumption,highfrequency(upto1MHZ),vibrationresistance,notafraidofpollutionorcorrosionbydust,oil,watervaporandsaltspray.
Hydraulic
Classification
Hydrauliccomponentsmainlyincludeone-wayvalve,pressurereducingvalve,overflowvalve,pressureregulatingvalve,flowregulatingvalve,hydrauliccylinderhydraulicPumps,hydraulicmotorvalves(pressurevalves,flowvalves,reversingvalves),hydraulicaccessories(oilfilterdevices,sealingrings,pipejoints),andreversingvalves,solenoidvalves,etc.
Uses
Hydrauliccomponentshaveawiderangeofuses.Hydraulicpressmanufacturers,aswellasmetallurgicalsteelcompanies,usethemmoreoften,andtheyareanimportantpartofautomationequipment.
Pneumatic
Classification
Pneumaticcomponentsaregenerallydividedinto:cylinder,quickconnector,cylinderflowrestrictor,pneumaticdelayvalve,filter,PUhose,Miniaturejoints,universalthreadedjoints,pneumaticvalves,dryers,pressurereliefvalves+solenoidvalvecontrol+cylinders,etc.
Application
Pneumaticcomponentscanbeusedin:foodindustry,clothingindustry,printingindustry,semiconductorindustry,automobileindustry.Ifyouputthepneumaticairsourcepart(compressedair,vacuum,airFilterunit);controlpart(varioussolenoidvalves,pneumaticvalves,manualvalves,speedcontrolvalves,on-offvalves,reliefvalves,pressurereducingvalves),executiveparts(pneumaticsuctioncups,cylinders,pneumaticfingers,etc.)connectedtogetherIfyoulookatit,youwillfindthatthemovementrealizedbyelectricenergycanberealizedbypneumatic.
Disadvantages
However,thedisadvantagesofpneumaticcomponentsarepoorpositioningaccuracy(duringoperation)andhighnoise.
InFLASHanimationproduction,weoftenneedtousecomponents.
Definition
Acomponentisagraphic,buttonorasmallanimationthatcanberepeatedlytakenout.Thesmallanimationinthecomponentcanbeplayedindependentlyofthemainanimation,andeachcomponentcanbemultipleindependentAcombinationofelements.Toputitbluntly,acomponentisequivalenttoareusabletemplate,andusingacomponentisequivalenttoinstantiatingacomponententity.Theadvantageofusingcomponentsisthattheycanbereused,reducingfilestoragespace.
Function
TherearemanytimesintheFLASHthatneedtoreusematerials,thenwecanconvertthematerialsintocomponents,orsimplycreatenewcomponents.Inordertofacilitaterepeateduseoreditandmodifyagain.Componentscanalsobeunderstoodasoriginalmaterials,whichareusuallystoredinacomponentlibrary.Theelementcanbemodifiedagain,butmodifyingtheelementinthescenewillnotmodifythepropertiesoftheelementitself.
Componentsusuallyhavethreeforms:Buttoncomponents.
Itisasegmentofflashanimation,whichcanbeplayedindependentlyofthemainanimation.Themovieclipcanbeanintegralpartofthemainanimation.Whenthemainanimationisplayed,themovieclipcomponentwillalsobeplayedinaloop.
Themoviefragmentsintheflashmoviehavetheirowntimelineandattributes.Itisinteractiveandisthemostversatileandfunctionalpart.Itcancontainexamplesofinteractivecontrols,sounds,andothermovieclips,anditcanalsobeplacedinthetimelineofthebuttoncomponenttocreateananimationbutton.
Buttoncomponents:interactivecontrolbuttonsusedtocreateanimationstocorrespondtothemousetime(suchasclick,release,etc.).Thebuttonhasfourdifferentstateframesofup,over,down,andhit.Differentcontentcanbecreatedonthedifferentstateframesofthebutton.Itcanbeastillgraphicoramovieclip,anditcangivethebuttonfieldtime.Interactiveactionsmakethebuttonshaveinteractivefunctions.
Graphiccomponent:Agraphiccomponentisareusablegraphic,whichcanbeacomponentofamovieclipcomponentorascene.Thegraphicelementisastillpicturewithoneframe,whichisoneofthebasicelementsformakinganimation,butitcannotaddinteractivebehaviorandsoundcontrol.
Graphicelementsinflasharesuitableforthereuseofstaticimages,ortocreateanimationsassociatedwiththemaintimeline.Itcannotprovideaninstancename,norcanitbereferencedinActionScript.
Method1:Createanewblankcomponent,andtheninsertthecontentofthecomponentinthecomponenteditingstate.Selectthemenu"Insert"->"NewComponent"orpressthekeyboardctrl+F8tocreateanewcomponent.
Method2:Convertobjectsonthesceneintocomponents.Selectanexistingcomponentinthescene,clicktherightmousebutton,andselectConverttocomponent.
Method3:Convertanimationtocomponents.
Eachcomponenthasamaximumpowerlimit,whetheritisanactivedevice(suchasamplifier)orPassivecomponents(suchascablesorfilters).Understandinghowpowerflowsinthesecomponentshelpstohandlehigherpowerlevelswhendesigningcircuitsandsystems.
Howmuchpowercanithandle?Thisisanunavoidablequestiontomostofthecomponentsinthetransmitter,andthequestionisusuallypassivecomponents,suchasfilters,Couplerandantenna.However,withthepowerlevelofmicrowavevacuumtubes(suchastravelingwavetubes(TWT))andcoreactivedevices(suchassiliconlaterallydiffusedmetaloxidesemiconductor(LDMOS)transistorsandgalliumnitride(GaN)fieldeffecttransistors(FET))Wheninstalledinawell-designedamplifiercircuit,theywillalsobelimitedbythepowerhandlingcapabilitiesofcomponentssuchasconnectorsandevenprintedcircuitboard(PCB)materials.Understandingthelimitationsofthedifferentcomponentsthatmakeupahigh-powercomponentorsystemcanhelpanswerthislong-standingquestion.
Thetransmitterrequiresthepowertobewithinthelimit.Generallyspeaking,theselimitsarestipulatedbygovernmentagencies,suchasthecommunicationstandardsestablishedbytheFederalCommunicationsCommission(FCC)intheUnitedStates.Butin"unregulated"systems,suchasradarandelectronicwarfare(EW)platforms,therestrictionsaremainlyduetotheelectroniccomponentsinthesystem.
Whencurrentflowsthroughthecircuit,partoftheelectricalenergywillbeconvertedintoheat.Circuitsthathandlelargeenoughcurrentswillheatup-especiallyinplaceswithhighresistance,suchasdiscreteresistors.Thebasicideaofsettingpowerlimitsforcircuitsorsystemsistouselowoperatingtemperaturestopreventanytemperaturerisethatmaydamagethecircuitorsystemcomponentsormaterials,suchasthedielectricmaterialsusedinprintedcircuitboards.Interruptionswhencurrent/heatflowsthroughthecircuit(suchaslooseorsolderedconnectors)canalsocausethermaldiscontinuitiesorhotspots,whichcancausedamageorreliabilityissues.Temperatureeffects,includingdifferencesinthecoefficientofthermalexpansion(CTE)betweendifferentmaterials,canalsocausereliabilityproblemsinhigh-frequencycircuitsandsystems.
Theheatalwaysflowsfromthehighertemperatureareatothelowertemperaturearea.Thisprinciplecanbeusedtotransfertheheatgeneratedbythehigh-powercircuitawayfromtheheatsource,suchasatransistororTWT.Ofcourse,theheatdissipationpathfromtheheatsourceshouldincludeadestinationcomposedofmaterialsthatcanclearordissipateheat,suchasametalgroundlayeroraheatsink.Inanycase,thethermalmanagementofanycircuitorsystemcanonlybeoptimallyachievedifitisconsideredatthebeginningofthedesigncycle.
Generally,thermalconductivityisusedtocomparetheperformanceofmaterialsusedtomanageheatinRF/microwavecircuits.Thisindexismeasuredbythepower(W/mK)appliedpermeterofmaterialperdegree(inKelvin).Perhapsthemostimportantfactorofthesematerialsforanyhigh-frequencycircuitisthePCBstackup,whichgenerallyhaslowthermalconductivity.Forexample,FR4laminatematerialsoftenusedinlow-costhigh-frequencycircuits,theirtypicalthermalconductivityisonly0.25W/mK.
Incontrast,copper(depositedonFR4asagroundplaneorcircuittrace)hasathermalconductivityof355W/mK.Copperhasalargeheatflowcapacity,whileFR4hasalmostnegligiblethermalconductivity.Inordertopreventhotspotsonthecoppertransmissionline,itisnecessarytoprovideahighthermalconductivitypathfromthetransmissionlinetothegroundplane,heatsinkorsomeotherhighthermalconductivityarea.ThinnerPCBmaterialallowsshorterpathstothegroundplane,becauseplatedvias(PTH)canbeusedtoconnectthecircuittracestothegroundplane.
Ofcourse,thepowerhandlingcapabilityofaPCBisafunctionofmanyfactors,includingconductorwidth,groundplanespacing,andmaterialdissipationfactor(loss).Inaddition,thedielectricconstantofthematerialwilldeterminethecircuitsizeatagivenidealcharacteristicimpedance,suchas50Ω,somaterialswithhigherdielectricconstantvaluesallowcircuitdesignerstoreducethesizeoftheirRF/microwavecircuits.Inotherwords,theseshortermetaltracesmeanthatPCBdielectricmaterialswithhigherthermalconductivityarerequiredtoachievecorrectthermalmanagement.
Underagivenapplicationpowerlevel,circuitmaterialswithhigherthermalconductivityhavealowertemperaturerisethanmaterialswithlowerthermalconductivity.Unfortunately,FR4isnodifferentfrommanyotherPCBmaterialswithlowthermalconductivity.However,theheattreatmentandpowerhandlingcapabilitiesofthecircuitcanbeimprovedbyspecifyingtheuseofPCBmaterialsthathaveahigherthermalconductivitythanFR4atleast.
Forexample,althoughthethermalconductivityofcopperhasnotyetreachedthelevel,severalofRogers’PCBmaterialscanprovidemuchhigherthermalconductivitythanFR4.ThethermalconductivityofRO4350Bmaterialis0.62W/mK,whilethecompany’sRO4360laminatehasathermalconductivityof0.80W/mK.Althoughthereisnosignificantimprovement,itdoeshavetwotothreetimestheheat/powercapacityimprovementcomparedwithFR4stack,whichcanrealizetheeffectivedissipationoftheheatgeneratedbytheRF/microwavecircuit.Thesetwomaterialsareparticularlysuitableforamplifierapplicationswithabuilt-inheatsource(transistor).Theybothhavealowcoefficientofthermalexpansion(CTE)value,sotheycanminimizedimensionalchangeswithtemperature.
Manycommercialcomputer-aidedengineering(CAE)softwaredesignpackagescanmodeltheheatflowthroughtheRF/microwavecircuitunderthegivenapplicationpowerlevelandthegivencircuitparametersettings,includingtheheatofthePCB.Conductivity.Thesesoftwaredesignpackagescontainmanyindividualprograms,suchasSonnetSoftware’selectromagneticsimulation(EM)tool,Fluent’sIcePaksoftware,ANSYS’TASPCBsoftware,andFlomerics’Flothermsoftware.Theyalsoincludemanydesignsoftwaretoolsuites,suchasAgilent'sAdvancedDesignSystem(ADS),ComputerSimulationTechnology(CST)'sCSTMicrowaveStudio,andAWR'sMicrowaveOffice.
ThesesoftwaretoolscanevenbeusedtostudytheimpactofdifferentworkingenvironmentsonthepowerprocessingcapabilitiesofRF/microwavecircuits,suchasthosethatmayoccuratsufficientlyhighpowerlevelsintheaircraft’slowatmosphericpressureorhighaltitudeenvironmentArc.TheseprogramscanalsoimprovethepowerhandlingcapabilitiesofdiscreteRF/microwavecomponentsbymodelingthefielddistributionofenergyflowingthroughcomponents(suchascouplersorfilters).
Ofcourse,PCBmaterialisnottheonlyfactorthataffectsheatflowinRF/microwavecircuitsorsystems.Thelimitationsofcablesandconnectorsonpower/heatinhighfrequencysystemsarealsowellknown.Inacoaxialassembly,theconnectorcanusuallyhandlemoreheat/powerthanthecabletowhichitisconnected,anddifferentconnectorshavedifferentpowerratings.Forexample,thepowerratingoftheN-typeconnectorisslightlyhigherthanthatoftheSMAconnectorwithasmallersize(andhigherfrequencyrange).Theaveragepowerandpeakpowerofcablesandconnectorsarerated,andthepeakpowerisequaltoV2/Z,whereZisthecharacteristicimpedanceandVisthepeakvoltage.Asimplemethodofestimatingtheaveragepowerratingistomultiplythepeakpowerratingofthecableassemblybythedutycycle.
ManycablesupplierssuchasAstrolabhavedevelopedspecialcalculationprogramstocalculatethepowerhandlingcapacityoftheircoaxialcableassemblies.Somecompanies,suchasTimesMicrowaveSystems,providefreedownloadablecalculationprogramsthatcanbeusedtopredictthepowerhandlingcapabilitiesoftheirowndifferenttypesofcoaxialcables.
Itisworthnotingthatthisisanextremelysimplistictreatmentofcomplextopics.Italsodoesnotcovertopicssuchasmaterialbreakdownvoltage,PCBdissipationfactor(dissipationfactor),howthecircuit’spowerhandlingcapacityisaffected,theimpactonPCBmaterialcoefficientofthermalexpansion(CTE)performance,andthedifferenceinheatingeffectsbetweencontinuouswaveandpulsedenergysources.
Incomponents,circuits,andsystems,therearemanycomplexphenomenathatmayaffectthepowerprocessingcapabilities,includingcomponentswithdifferentRF/microwavepowercapabilitiessuchasswitcheswith"on"and"off"states.Inadditiontosoftwareprograms,toolsthatcanbeusedforthermalanalysiscanalsoprovidethermalimagingcapabilitiesbasedoninfrared(IR)technology,whichcanbeusedtosafelystudyheataccumulationincomponents,circuits,andsystems.