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TDA2030DescriptionTheTDA2030isamonolithicintegratedcircuitinPentawattpackage,intendedforuseasalow-frequencyclassABamplifier.Typicallyitprovides14Woutputpower(d=0.5%)at14V/4Ω;at14Vor28V,theguaranteedoutputpoweris12Wona4Ωloadand8Wonan8Ω(DIN45500).TheTDA2030provideshighoutputcurrentandhasverylowharmonicandcross-overdistortion.Further,thedeviceincorporatesanoriginal(andpatented)shortcircuitprotectionsystemcomprisinganarrangementforautomaticallylimitingthedissipatedpowersoastokeeptheworkingpointoftheoutputtransistorswithintheirsafeoperatingarea.Aconventionalthermalshut-downsystemisalsoincluded.HowToMakeHighPowerAmplifierUsingTDA2030/DC12v(EnglishSubtitle)CatalogTDA2030DescriptionTDA2030PinConfigurationsTDA2030FunctionalBlockDiagramTDA2030PackageOutlineTDA2030FeaturesTDA2030FunctionalEquivalentsTDA2030PopularitybyRegionTDA2030ApplicationsWheretoUseTDA2030?HowtoUseTDA2030?ProductManufacturerComponentDatasheetOrdering&QuantityTDA2030PinConfigurationsPinNumberPinNameDescription1NonInvertingInputNon-invertingend(+)ofAmplifier2InvertingInputInvertingend(-)ofAmplifier3Vs(Ground)Connecttothegroundofthecircuit4OutputThispinoutputstheamplifiedsignal5Vs(Power)Supplyvoltage,Minimum6VandMaximum36VTDA2030FunctionalBlockDiagramTDA2030PackageOutlineMechanicalData:TDA2030FeaturesFewexternalcomponentsMinimalbootimpactLow-frequencyclassABamplifier,mostsuitableforaudioamplificationCanprovideupto20wattsofoutputpowerWiderangepowersupplyfrom6Vto36VCanprovideshortcircuitandthermalprotectionBreadboardfriendlyAvailablein5-pinTO220packageTDA2030FunctionalEquivalentsTDA2030PopularitybyRegionTDA2030ApplicationsForaudiosignalamplificationSuitableforhighpoweramplificationAbletorunondual/splitpowersuppliesCanbeusedtocascadeaudiospeakersWheretouseTDA2030?TheTDA2030isapowerfulaudioamplifierIC.Anaudioamplifierisnothingbutonethathasthecapabilitytoamplifytheaudiosignalsfromanyaudiosourcesuchasmobilephonejackormicrophonesothatvolumeisincreasedwhentheaudioisplayedinaspeaker.Audioamplifiercircuitscanalsobemadeusingsimpleop-amps,butifyouneedthehighervolumethatisloudenoughforaroomthenthispoweraudioamplifieriswillbethebestchoice.ThisICcandeliverupto20Wofoutputpower,soyoucanruna4Ωspeakerat12Woran8Ωspeakerat8W.HowtouseTDA2030?TheTDA2030isbreadboardfriendlyandhencecanbeeasilytestedusingabreadboard.TheTDA2030AdatasheetgiveninthepaperconsistsofsomebasiccircuitswhichcanbeusedtomakethisICwork.Ihavealsogivenaverybasiccircuitbelow.TheICcanwitherworkondualpowersupplyorsinglemodepowersupply,tokeepthissimpleIhavepreferredsingle-modesupplybyusinga9Vbattery.The5thpin(Vs)isconnectedtothepositiveterminalofthebatteryandthe3rdpin(Ground)isconnectedtothenegativeterminalofthebattery.ThisICisapoweramplifierICandhencerequiresadecentamountofcurrenttooperate,hencemakesureyourbatterycansourceenoughcurrent.TheresistorR1andR2formapotentialdivideracrossthepins4and2.ThetwodiodesD1andD2areusedtoprotecttheICfromreversecurrents.ThespeakerLS1canbeanyordinaryspeakerofvalue4Ω,6Ωor8Ω.TheaudiosourceC2(1)canbeanyaudiosourcefromamobilejackorevenamicrophone.JustconnectthepositivepointtoC2(1)andgroundtheotherpoint.Also,notethatthisamplifiercanamplifyonlymonochannelsoundsignals.Soifyouhavetwoaudiowiresforleftandrightchannelcombinethembothtomakeitasasinglechannel.ProductManufacturerTheSTMicroelectronics(SGS-THOMSON,ST)groupwasestablishedin1987bythemergerofSGSMicroelectronicsinItalyandThomsonSemiconductorinFrance.InMay1998,SGS-THOMSONMicroelectronicschangeditscompanynametoSTMicroelectronicsCo.,Ltd.STMicroelectronicsisoneoftheworldslargestsemiconductorcompanies.Itaimstobethemarketleaderinmultimediaapplicationintegrationandpowersolutions.STMicroelectronicshastheworldsmostpowerfulproductlineup,includingdedicatedproductswithhighintellectualpropertyrights.Products,therearealsoinnovativeproductsinmanyfields,suchasdiscretedevices,high-performancemicrocontrollers,securitysmartcardchips,andmicro-electromechanicalsystems(MEMS)devices.Indemandingapplicationssuchasmobilemultimedia,set-topboxesandcomputerperipherals,STMicroelectronicsisapioneerinthedevelopmentofcomplexICsusingplatform-baseddesignmethods,andcontinuestoimprovethisdesignmethod.STMicroelectronicshasawell-balancedproductportfoliothatcanmeettheneedsofallmicroelectronicsusers.Globalstrategiccustomerssystem-on-chip(SoC)projectsalldesignateSTMicroelectronicsasthepreferredpartner.Atthesametime,thecompanyalsoprovidesfullsupportforlocalcompaniestomeetlocalcustomersneedsforgeneral-purposedevicesandsolutions.ComponentDatasheetTDA2030Datasheet

TDA2030DescriptionTheTDA2030isamonolithicintegratedcircuitinPentawattpackage,intendedforuseasalow-frequencyclassABamplifier.Typicallyitprovides14Woutputpower(d=0.5%)at14V/4Ω;at14Vor28V,theguaranteedoutputpoweris12Wona4Ωloadand8Wonan8Ω(DIN45500).TheTDA2030provideshighoutputcurrentandhasverylowharmonicandcross-overdistortion.Further,thedeviceincorporatesanoriginal(andpatented)shortcircuitprotectionsystemcomprisinganarrangementforautomaticallylimitingthedissipatedpowersoastokeeptheworkingpointoftheoutputtransistorswithintheirsafeoperatingarea.Aconventionalthermalshut-downsystemisalsoincluded.HowToMakeHighPowerAmplifierUsingTDA2030/DC12v(EnglishSubtitle)CatalogTDA2030DescriptionTDA2030PinConfigurationsTDA2030FunctionalBlockDiagramTDA2030PackageOutlineTDA2030FeaturesTDA2030FunctionalEquivalentsTDA2030PopularitybyRegionTDA2030ApplicationsWheretoUseTDA2030?HowtoUseTDA2030?ProductManufacturerComponentDatasheetOrdering&QuantityTDA2030PinConfigurationsPinNumberPinNameDescription1NonInvertingInputNon-invertingend(+)ofAmplifier2InvertingInputInvertingend(-)ofAmplifier3Vs(Ground)Connecttothegroundofthecircuit4OutputThispinoutputstheamplifiedsignal5Vs(Power)Supplyvoltage,Minimum6VandMaximum36VTDA2030FunctionalBlockDiagramTDA2030PackageOutlineMechanicalData:TDA2030FeaturesFewexternalcomponentsMinimalbootimpactLow-frequencyclassABamplifier,mostsuitableforaudioamplificationCanprovideupto20wattsofoutputpowerWiderangepowersupplyfrom6Vto36VCanprovideshortcircuitandthermalprotectionBreadboardfriendlyAvailablein5-pinTO220packageTDA2030FunctionalEquivalentsTDA2030PopularitybyRegionTDA2030ApplicationsForaudiosignalamplificationSuitableforhighpoweramplificationAbletorunondual/splitpowersuppliesCanbeusedtocascadeaudiospeakersWheretouseTDA2030?TheTDA2030isapowerfulaudioamplifierIC.Anaudioamplifierisnothingbutonethathasthecapabilitytoamplifytheaudiosignalsfromanyaudiosourcesuchasmobilephonejackormicrophonesothatvolumeisincreasedwhentheaudioisplayedinaspeaker.Audioamplifiercircuitscanalsobemadeusingsimpleop-amps,butifyouneedthehighervolumethatisloudenoughforaroomthenthispoweraudioamplifieriswillbethebestchoice.ThisICcandeliverupto20Wofoutputpower,soyoucanruna4Ωspeakerat12Woran8Ωspeakerat8W.HowtouseTDA2030?TheTDA2030isbreadboardfriendlyandhencecanbeeasilytestedusingabreadboard.TheTDA2030AdatasheetgiveninthepaperconsistsofsomebasiccircuitswhichcanbeusedtomakethisICwork.Ihavealsogivenaverybasiccircuitbelow.TheICcanwitherworkondualpowersupplyorsinglemodepowersupply,tokeepthissimpleIhavepreferredsingle-modesupplybyusinga9Vbattery.The5thpin(Vs)isconnectedtothepositiveterminalofthebatteryandthe3rdpin(Ground)isconnectedtothenegativeterminalofthebattery.ThisICisapoweramplifierICandhencerequiresadecentamountofcurrenttooperate,hencemakesureyourbatterycansourceenoughcurrent.TheresistorR1andR2formapotentialdivideracrossthepins4and2.ThetwodiodesD1andD2areusedtoprotecttheICfromreversecurrents.ThespeakerLS1canbeanyordinaryspeakerofvalue4Ω,6Ωor8Ω.TheaudiosourceC2(1)canbeanyaudiosourcefromamobilejackorevenamicrophone.JustconnectthepositivepointtoC2(1)andgroundtheotherpoint.Also,notethatthisamplifiercanamplifyonlymonochannelsoundsignals.Soifyouhavetwoaudiowiresforleftandrightchannelcombinethembothtomakeitasasinglechannel.ProductManufacturerTheSTMicroelectronics(SGS-THOMSON,ST)groupwasestablishedin1987bythemergerofSGSMicroelectronicsinItalyandThomsonSemiconductorinFrance.InMay1998,SGS-THOMSONMicroelectronicschangeditscompanynametoSTMicroelectronicsCo.,Ltd.STMicroelectronicsisoneoftheworldslargestsemiconductorcompanies.Itaimstobethemarketleaderinmultimediaapplicationintegrationandpowersolutions.STMicroelectronicshastheworldsmostpowerfulproductlineup,includingdedicatedproductswithhighintellectualpropertyrights.Products,therearealsoinnovativeproductsinmanyfields,suchasdiscretedevices,high-performancemicrocontrollers,securitysmartcardchips,andmicro-electromechanicalsystems(MEMS)devices.Indemandingapplicationssuchasmobilemultimedia,set-topboxesandcomputerperipherals,STMicroelectronicsisapioneerinthedevelopmentofcomplexICsusingplatform-baseddesignmethods,andcontinuestoimprovethisdesignmethod.STMicroelectronicshasawell-balancedproductportfoliothatcanmeettheneedsofallmicroelectronicsusers.Globalstrategiccustomerssystem-on-chip(SoC)projectsalldesignateSTMicroelectronicsasthepreferredpartner.Atthesametime,thecompanyalsoprovidesfullsupportforlocalcompaniestomeetlocalcustomersneedsforgeneral-purposedevicesandsolutions.ComponentDatasheetTDA2030Datasheet

I.DesriptionInthefieldofmeasurementandcontrol,itisoftenencounteredthattheoutputsignalofthemonitoredobjectissmall,anditisdifficulttodirectlycollectit.Generally,itneedstobeamplifiedbeforeprocessing.Thisarticleintroducesamethodofimplementingasmallsignalacquisitionsystem.Thesmallestsystemisrealizedbyusingthesingle-chipSTC25A60S2withA/Dconversionfunctionandtheeasy-to-useamplifierAD620withpreciseamplificationfunction.Thesystemdesignandimplementationarediscussedandtheacquisitionisintroducedindetail.Theprocessofsmallsignal,andgivespracticalapplicationexamples,aswellastheapplicationofsmallsignalacquisitioninrelatedfields.AD620CatalogI.DesriptionII.AD620IntroductionIII.IntroductiontoSTC12C5A60S2IV.SystemHardwareDesign4.1SystemPrincipleBlockDiagram4.2PowerSupplyCircuitDesign4.3SignalConditioningCircuit4.4SystemDecouplingCircuit4.5RealizationofA/DConversion4.6Follow-upWorkV.PracticalApplicationVI.ConclusionFAQOrdering&QuantityII.AD620IntroductionAsamonolithicinstrumentamplifier,AD620haslowpowerconsumption,achipwithhighgainthroughexternalresistors,andfeatureslowinputdriftandtemperaturedrift.AD620isdevelopedfromthetraditionalthreeoperationalamplifiers,butsomeofthemainperformanceisbetterthanthedesignoftheinstrumentamplifiercomposedofthreeoperationalamplifiers,suchaswidepowersupplyrange(2.3~18V),smalldesignvolume,andverypowerconsumptionLow(themaximumpowersupplycurrentisonly1.3mA),soitissuitableforlow-voltage,low-powerapplications.Figure1SchematicdiagramofAD620principleThemonolithicstructureandlasercrystaladjustmentofAD620allowcircuitcomponentstobecloselymatchedandtracked,therebyensuringtheinherenthighperformanceofthecircuit.AD620isathree-op-ampintegratedinstrumentationamplifierstructure.Inordertoprotectthehighprecisionofgaincontrol,theinputtransistorprovidesasimpledifferentialbipolarinput,andusestheprocesstoobtainalowerinputbiascurrent.Throughtheinputstageinternalop-ampThefeedbacktokeepthecollectorcurrentoftheinputtransistorconstant,andtheinputvoltageisaddedtotheexternalgaincontrolresistorRG.ThetwointernalgainresistorsofAD620are24.7k8,sothegainequationis:G=49.4k/RG+1(1)Fortherequiredgain,theexternalcontrolresistancevalueis:RG=49.4/(G-1)k(2)III.IntroductiontoSTC12C5A60S2STC12C5A60S2isanewgeneration8051single-chipmicrocomputerwithA/Dconversionfunction.Theinstructioncodeisfullycompatiblewiththetraditional8051,butthespeedis8-12timesfaster.With8channelsofhigh-speed10-bitinputA/Dconversion(250k/s),itcanbeusedfortemperaturedetection,batteryvoltagedetection,keyscanning,spectrumdetection,etc.TheusercansetanychannelasA/Dconversion,andtheportsthatdonotneedtobeusedasA/DcancontinuetobeusedasI/Oports.Itscharacteristicsareasfollows:Figure2STC12C5A60S2(1)On-chipintegrated1280bytesRAM;(2)WithEEPROMfunction(STC12C5A62S2/AD/PWMwithoutinternalEEPROM);(3)Enhanced8051CPU,1T,singleclock/machinecycle,instructioncodeisfullycompatiblewithtraditional8051;(4)InternalintegratedMAX810dedicatedresetcircuit(whentheexternalcrystalisbelow12M,theresetpincanbedirectlyconnectedtothegroundwith1Kresistance);(5)Userapplicationspace8K/16K/20K/32K/40K/48K/52K/60K/62Kbytes;(6)ISP(In-SystemProgrammable)/IAP(In-ApplicationProgrammable),noneedforadedicatedprogrammer,noneedforadedicatedemulator,youcandownloadtheuserprogramdirectlythroughtheserialport(P3.0/P3.1),andonepiececanbecompletedinafewseconds;(7)STC12C5A60S2serieshavedualserialports,onlythosewiththeS2logosuffixhavedualserialports,RxD2/P1.2(canbesettoP4.2byregister),TxD2/P1.3(canbesettoP4.3byregister);(8)GeneralI/Oports(36/40/44),afterreset,theyare:quasi-bidirectionalport/weakpull-up(normal8051traditionalI/Oport),whichcanbesettofourmodes:quasi-bidirectionalport/weakPull-up,push-pull/strongpull-up,onlyinput/highimpedance,open-drain,eachI/Oportdrivecapacitycanreach20mA,butthewholechipshouldnotexceed120mA;(9)A/Dconversion,10-bitprecisionADC,8channelsintotal,conversionspeedupto250K/S(250,000timespersecond),universalfull-duplexasynchronousserialport(UART),becausetheSTC12seriesishigh-speed8051,canreusetimerorPCAsoftwaretorealizemultipleserialports.IV.SystemHardwareDesign4.1SystemPrincipleBlockDiagramGenerallyspeaking,beforethesignalisused,itneedstobefilteredandthenamplified,oramplifiedandthenfiltered,andthenobtained/perceivedbymeanssuchasA/D.Forsmallsignals,thesignalamplitudeisonlyafewmillivoltsorevensmaller.Iffilteredfirst,usefulsignalsmaybefilteredout.Therefore,inthiscase,youneedtoamplifyfirst,thenfilter,andthenperformA/Dconversionorotherprocessing.Accordingtothecharacteristicsofthissystem,theinterferenceinthesystemcanbeignored,sothesignalfilteringlinkisnotconsidered.Therefore,thesystemismainlyrealizedthroughthreeimportantlinks:signalextraction,signalamplification,andA/Dacquisition.Thedatageneratedinthethirdlinkcanguidepeoplesworkordisplayrelevantinformation.TheblockdiagramoftheentiresystemisshowninFigure3.Figure3Systemblockdiagram4.2PowerSupplyCircuitDesignAD620amplifiercanusesinglepowersupplyordualpowersupply,butwhenusingdualpowersupply,itsperformanceisbetterthansinglepowersupply.Inintegratedcircuitdesign,singlepowersupplyiseasytoimplement,butconsideringtheworkingperformanceofthechip,dualpowersupplyisusedinthissystem.UsetheICL7660Schiptoconvertanexternalsinglepowersupplyintoadualpowersupply.ICL7660Sisavoltageconversionchipthatcanrealizethefunctionofconvertingapositivevoltagetoanegativevoltage,anditsperipheralcircuitisrelativelysimple.ThespecificcircuitisshowninFigure4.Figure4PowersupplyimplementationschematicdiagramTheotherchipsinthesystemarepoweredbyasingle5Vpowersupply,andtheconnected5Vpowersupplycanbeusedwithoutanyprocessing,whichisnotdescribedhere.4.3SignalConditioningCircuitTheactualweaksignalisgenerallymVlevelorevensmaller.Beforeprocessing,itneedstobeamplifiedandthenA/Dcollected.AccordingtotheA/DfunctionofSTC12C5A60S2,itisnecessarytoaccuratelyamplifythesignaltoreachtheVlevel,sotheAD620amplifierisused.AD620hasagoodamplificationeffecton2inputdifferentialsignals.Inpracticalapplications,thesignalsaregenerallygeneratedbyelectricbridges.Inordertorealizesignalamplification,AD620needsanexternalresistor,whichdeterminestheamplificationfactortogetherwiththeinternalresistor.SupposethemagnificationisG,thenthereisthefollowingformula.G=(RG/R1)+1(1)canalsobewrittenasthefollowingformula:G=49.4k/RG+1(2)1)Intheformula,RGistheinternalresistanceofAD620,andR1istheexternalresistance.Itcanbeseenfromtheformulas(1)and(2)thatthesizeofRGintheformula(1)is49.4k.Theconditionedsignalisoutputthroughthe6-pinofAD620.Atthistime,itcanbedirectlyconnectedtotheA/Dconversionchiptorealizedatacollection.Itcanbereducedbythecorrespondingmultiplewhenusingit.TheprincipleofsignalconditioningisshowninFigure5.Figure5Signalconditioningcircuit4.4SystemDecouplingCircuitSincethesystemmainlyrealizessmallsignalamplificationandA/Dconversionafteramplification,thechipthatcompletestheA/Dfunctionofthissystem,namelySTC12C5A60S2,usesitsownworkingpowersupplyasthereferencevoltage.Inordertoensuretheconsistencyoftheconversionresults,itisnecessarytoensurethepowersupplyvoltagestability.Tofilterouttheinterferenceinthepowersupply,itcanbefilteredbymultiplecapacitorsinparallel.Afterthecapacitorsareconnectedinparallel,thecapacitancevalueincreases,buttheequivalentresistanceinsidethecapacitorisreducedduetotheparallelconnection,whichisbeneficialtoreducetheloss.Therefore,manycapacitorsareusedinparallel,andtherealizationprincipleisshowninFigure6.Figure6Powerdecouplingcircuit4.5RealizationofA/DConversionAsmentionedearlier,STC12C5A60S2isasingle-chipmicrocomputerwithA/Dconversionfunction,whichisconvenient,simple,andmulti-functional.ItsA/Dconversiononlyrequires90clockcycles(relatedtoitsoperatingfrequency)atthefastest.ThissystemUseittoachieveA/Dconversion.STC12C5A60S2usesportP1asan8-channelA/Dconversioninputinterface.Whenusingit,youonlyneedtosetitasananaloginterface.Bysettingthecorrespondingregister,theA/Dconversioncanbecompleted.Theunusedpinscanstillbeusedasordinarytubes.ThissystemrealizestheA/Dconversionofoneinputsignal,soitonlyneedstosetone.Inthissystem,P1.0portisusedasthesignalinputport.ThissystemrealizestheprincipleofA/DconversionasshowninFigure7.Figure7A/Dacquisitioncircuit4.6Follow-upWorkAftertheA/Dconversioniscompleted,dataanalysisisrequired.Generally,itcanbesenttotheuppercomputerthroughthecommunicationport(usuallyserialport),andthedataisprocessedbytheuppercomputer.Accordingtothedifferentcharacteristicsofthespecificsystem,thedataprocessingmethodsarealsodifferent,soitsnoneedtodiscussthemindetailhere.Table1ADconversiondataandactualdataAfterthesystemperformsA/Dconversiononsignalsofdifferentsizes,aseriesofactualdataandtheoreticaldataareobtained,asshowninTable1.DrawthecurveofA/DdatathroughExcel,andfoundthatthesystemA/Dconverterhasgoodlinearity.AsshowninFigure8.Figure8LinearityofA/DconverterV.PracticalApplicationThesmallsignalconditioning,A/Dconversion,andprocessingmethodsarediscussedinmoredetailabove.Thespecificapplicationisintroducedbelowthroughexamples.Asakindofsensingelement,resistancestraingaugeiscommonlyusedtomonitorthedeformationoftheobject.Generally,thestraingaugeisattachedtothesidepointofthecomponent.Afterthecomponentisstressed,duetothestrainofthemeasuringpoint,theresistancechanges,resultinginaweakvoltagechange.Thevoltagechangecanbecalculatedtoobtainthedeformationdegreeofthecomponent,soastoachievethepurposeofmonitoringtheconditionofthecomponentandguidetherelevantengineeringpersonneltodealwithit.Thissystemcanbeappliedtothevoltagegeneratedbytheelectricbridge.AschematicdiagramoftheelectricbridgeisshowninFigure9.Inthefigure,R4,R3,R1,andR2arethefourarmsofthebridge,R4andR3arefixedresistancesofimpedance,andR1andR2areinOneisaresistorwhoseresistancevaluechangesafterbeingstressed.R4andR3havethesameresistancevalue,andR1andR2havethesameresistancevaluewhentheyarenotstressed.Inthecaseofnoforce,thetwopointsofthebridge3and4areequipotential,thatis,thepotentialdifferenceis0.IfitisinputasAD620,theinputsignalisconsideredtobe0,andthebridgeissaidtobebalancedatthistime.WhentheforceofR1orR2changes,theresultofthechangeisreflectedinitsresistancevalue,whichcanbeobtainedbyOhmslaw.Thepotentialatpoints3and4isdifferent,thatis,thereisapotentialdifference.Atthistime,thebridgeisoutofbalance,butatthistimeThesignalisveryweakandcannotbecollecteddirectly.Therefore,thesignalisamplifiedthroughthesignalconditioningcircuitmentionedinthearticle,thatis,points3and4inthebridgeareconnectedtopins2and3ofAD620,afteramplification,thenA/Dacquisitionisperformed.Figure9SchematicdiagramofelectricbridgeThissystemusesasimpleelectricbridgebuiltbyitselfduringsimulation,asshowninFigure10.Figure10SimpleelectricbridgeByadjustingR2inthefigure,differentweaksignalsaregenerated,andthesimplebridge1and2areconnectedtothesignalconditioningcircuit,andthenafterA/Dconversion,weaksignalacquisitioncanberealized.The1,2endsofthesimpleelectricbridgecorrespondtothe3and4endsinthefigure.Inthissimulation,adjustR2togenerateabout5.35mVatbothendsof1,2andadjusttheexternalresistanceinthesignalconditioningcircuitto160.7.Thecalculatedmagnificationisabout308.4times,andtheA/Dreferencevoltageis4.256VBymeasuringtheoutputofAD620,itcanbeobtainedthatthevoltageis1.645V,andthemagnificationfactorG=1.647V/5.35mV308canbecalculated.Itcanbeseenthatthemagnificationeffectisgood(afterremovingthemagnificationeffect,theerrorisonlynVlevel).ThroughmultipleA/Dconversions,thereturnedresultsareallaround0x018B,whichprovesthatthesystemhashighcredibility(ithasbeenusedinactualsystems).VI.ConclusionThisarticledescribesindetailthedesignandimplementationofsmallsignalacquisitionsystemsfromchipselection,circuitdesign,etc.,suchas8-bitsingle-chipSTC12C5A60S2asthecontrollerandA/Dconverter;AD620asthemainchipofthesignalconditioningcircuit;electricbridgeprincipleetc.Throughthetest,thecircuithasrealizeditsfunctionwell,andithasaccomplishedtheexpectedgoalexcellentlyintheactualsystem,whichhascertainpracticalvalue.FAQWhatisAD620?AD620isalow-cost,high-precisioninstrumentationamplifier.Itonlyrequiresanexternalresistortosetthegain.Thegainrangeis1to10,000.CanIchangeAD620toAD623whenmakingMCUproducts?BothAD620andAD623aresingleinstrumentationamplifiers,andthepinarrangementisexactlythesame.Themaindifferenceis:AD620mustusepositiveandnegativepowersupplies,AD623canbeapositiveandnegativepowersupplyorasinglepowersupply.IftheoriginalboardisAD620,youcanreplaceitwith623;iftheoriginalboardisAD623,youmaynotbeabletoreplaceitwith620(itdependsonwhetherthepowersupplyoftheoriginalboardcircuitisdualpowersupplyorsinglepowersupply).AfterreplacingAD620andAD623insingle-chipproducts,theprogramcanworknormallywithoutmodification.WhatisthedifferencebetweenAD620BRandAD620AN?Theirpackagesaredifferent.WhatistheoutputresistanceofAD620?Howtoadjustit?AD620isakindoflowpowerconsumptioninstrumentamplifier,itsoutputresistanceisabout10K,thisistheinherentcharacteristicofthischip,generallyitisdifficulttoadjust.Ifyouhaverequirementsforoutputresistance,youcangenerallyuseanexternalcircuittosolveit.IsAD620apositivephaseamplificationorareversephaseamplification?AD620isaninstrumentamplifier,theoutputvoltageis[(Vin+)-(Vin-)]*gain.Ifthedesiredsignalis(Vin+)-(Vin-),thegainispositive,whichisequivalenttopositiveamplification.Conversely,ifthedesiredsignalis(Vin-)-(Vin+),thegainisequivalenttonegative,whichisequivalenttoreverseamplification.Whatisaninstrumentationamplifier?Instrumentationamplifier,animprovementofthedifferentialamplifier,hasaninputbuffer,doesnotrequireinputimpedancematching,sothattheamplifierissuitableformeasurementandelectronicinstrumentsDescriptionThe2N7000isaN-ChannelEnhancementModeFieldEffectTransistor,a.k.a.MOSFETforvoltagecontrolledsmallsignalswitching.2N7000NChannelEnhancementModeMOSFETSwitchCircuitBasicsCatalogDescription2N7000Pinout2N7000Parameters2N7000Features2N7000Applications2N7000Advantage2N7000SwitchingWaveformsandTestCircuit2N7000PackageInformation2N7000PopularitybyRegion2N7000AlternativesHowtouse2N7000Wheretouse2N7000ProductManufacturerFAQOrdering&Quantity2N7000PinoutPinNumberPinNameDescription1SourceCurrentflowsoutthroughSource2GateControlsthebiasingoftheMOSFET3DrainCurrentflowsinthroughDrain2N7000ParametersConfigurationSINGLEWITHBUILT-INDIODEContinuousDrainCurrent(ID)200mADrainCurrent-Max(ID)0.2ADraintoSourceResistance5RDraintoSourceVoltage(Vdss)60VDrain-sourceOnResistance-Max5DSBreakdownVoltage-Min60VElementConfigurationSingleFeedbackCap-Max(Crss)5pFFETTechnologyMETAL-OXIDESEMICONDUCTORGatetoSourceVoltage(Vgs)30VHeight5.33mmJEDEC-95CodeTO-92JESD-30CodeO-PBCY-T3LeadFreeLeadFreeLength5.21mmManufacturerMicrochipTechnologyIncManufacturerPartNumber2N7000-GP003MaxPowerDissipation1WNumberofChannels1NumberofElements1NumberofTerminals3OperatingModeENHANCEMENTMODEOperatingTemperature-Max150COperatingTemperature-Min-55CPackageTO-92-3PartLifeCycleCodeActivePolarity/ChannelTypeN-CHANNELReachComplianceCodeCompliantREACHSVHCNoSVHCRiskRank5.56SurfaceMountNOTerminalFormTHROUGH-HOLETerminalPositionBOTTOMTransistorApplicationSWITCHINGTransistorElementMaterialSILICONVoltageRating(DC)60VWeight0.00776ozWidth4.19mm2N7000FeaturesFreefromsecondarybreakdownLowpowerdriverequirementEaseofparallelingLowCISSandfastswitchingspeedsExcellentthermalstabilityIntegralsource-draindiodeHighinputimpedanceandhighgain2N7000ApplicationsMotorcontrolsConvertersAmplifiersSwitchesPowersupplycircuitsDrivers(relays,hammers,solenoids,lamps,memories,displays,bipolartransistors,etc.)The2N7000hasbeenreferredtoasaFETlingtonandasanabsolutelyidealhackerpart.ThewordFETlingtonisareferencetotheDarlington-transistor-likesaturationcharacteristic.Atypicaluseofthesetransistorsisasaswitchformoderatevoltagesandcurrents,includingasdriversforsmalllamps,motors,andrelays.Inswitchingcircuits,theseFETscanbeusedmuchlikebipolarjunctiontransistors,buthavesomeadvantages:highinputimpedanceoftheinsulatedgatemeansalmostnogatecurrentisrequiredconsequentlynocurrent-limitingresistorisrequiredinthegateinputMOSFETs,unlikePNjunctiondevices(suchasLEDs)canbeparalleledbecauseresistanceincreaseswithtemperature,althoughthequalityofthisloadbalanceislargelydependentontheinternalchemistryofeachindividualMOSFETinthecircuitThemaindisadvantagesoftheseFETsoverbipolartransistorsinswitchingarethefollowing:susceptibilitytocumulativedamagefromstaticdischargepriortoinstallationcircuitswithexternalgateexposurerequireaprotectiongateresistororotherstaticdischargeprotectionNon-zeroohmicresponsewhendriventosaturation,ascomparedtoaconstantjunctionvoltagedropinabipolarjunctiontransistor2N7000AdvantageTheSupertex2N7000isanenhancement-mode(normallyoff)transistorthatutilizesaverticalDMOSstructureandSupertexswell-provensilicon-gatemanufacturingprocess.Thiscombinationproducesadevicewiththepowerhandlingcapabilitiesofbipolartransistors,andthehighinputimpedanceandpositivetemperaturecoefficientinherentinMOSdevices.CharacteristicofallMOSstructures,thisdeviceisfreefromthermalrunawayandthermally-inducedsecondarybreakdown.SupertexsverticalDMOSFETsareideallysuitedtoawiderangeofswitchingandamplifyingapplicationswhereverylowthresholdvoltage,highbreakdownvoltage,highinputimpedance,lowinputcapacitance,andfastswitchingspeedsaredesired.2N7000SwitchingWaveformsandTestCircuit2N7000PackageInformation3-LeadTO-92PackageOutline(N3)FrontView3-LeadTO-92PackageOutline(N3)SideView3-LeadTO-92PackageOutline(N3)BottomView2N7000PopularitybyRegion2N7000AlternativesManufacturerManufacturerPartNo.LifecycleStatusIndicatorMicrochipSupertex2N7000-GVolumeProductionHowtouse2N7000AMosfethasthreeterminals:Drain,SourceandGate.ThecurrentalwaysentersthroughtheDrainandleavesthroughtheSource.TheGatepinactsasaswitchtoturntheMosfetonoroff.IftheGateisconnectedtoground,theMosfetisswitchedoff,i.e.thereisnoconnectionbetweentheDrainandtheSource(open).IftheGateissuppliedwithitssourcevoltage(VGS)thentheMOSFETwillbeON,i.e.theDrainandSourcepinswillbeconnectedtogether(Closed).Thus,bycontrollingthevoltage(VGS),wecanswitchtheMOSFET,makingtheMOSFETavoltage-controlleddevice.Thegate-sourcevoltage(VGS)isacriticalparameterwhenusingthetransistor.Forthistransistor,theVGSis20V,sowhenwesupplythisvoltage,theMOSFETwillbecompletelyclosed.Anyvaluebetween20VcausestheMOSFETtopartiallyclose,creatingapartialconnection.TheloadswitchedbytheMOSFETcanreach60V(VDS)andcanconsumeupto200mA(ID).GivenbellowisaverysimplecircuitunderneaththatusesthisMOSFETtocontrola24V2Aloadmotor.Thecurrentandvoltagevaluescanalsobeobservedwhentheswitchisclosedandopen.AsweknowthatthevoltageofthegridsourceofthisMosfetis20V,weused20VtoturnontheMOSFET.Whenthegateswitchisopen,theMosfetsgatepinmustbeconnectedtogroundtocuttheload,soweuseda10KresistortoturnofftheMOSFETafterturningiton.TheRGresistorisacurrentlimitingresistorthatlimitstherequiredgridcurrent.IftheloadcontrolledbytheMOSFETisaninductiveloadlikethemotorwehaveusedhere,thenitismandatorytouseaflywheeldiodetosafelydischargetheloadaccumulatedbytheinductivecoil.Wheretouse2N70002N7000isasmallN-channelMOSFET.MOSFETsareelectronicpowerswitches,justliketransistors,butwithahighercurrentandvoltagerating.The2N7000MOSFETcanbeusedtoswitchloadsthatoperateonlessthan60V(VDS)and200mA(ID).ThismosfetcomesinacompactTO-92packageandhasathresholdvoltageof3V,soifyouarelookingforasmallmosfettoswitchaload,thisICmightberightforyou.ProductManufacturerMicrochipTechnologyInc.isaleadingproviderofmicrocontrollerandanalogsemiconductors,providinglow-riskproductdevelopment,lowertotalsystemcostandfastertimetomarketforthousandsofdiversecustomerapplicationsworldwide.HeadquarteredinChandler,Arizona,Microchipoffersoutstandingtechnicalsupportalongwithdependabledeliveryandquality.FAQWhatisa2n7000Mosfet?2N7000isasmallsignalN-channelMOSFET.MOSFETsarepowerelectronicswitchesjustliketransistors,butwithahighercurrentandvoltagerating.The2N7000MOSFETcanbeusedtoswitchloadswhichoperatesonlessthan60V(VDS)and200mA(ID).Whatisamaximumoperatingvoltageforthe2n7002transistor?The2N7002isalogiclevelMOSFETwithalowon-stateresistance.Themosfethasalowgatetosourcethresholdvoltageof2.1Vtypicallythismakesthemosfetsuitableevenfor3.3Vapplicationcircuits.WhatisMosfetgatethresholdvoltage?ThethresholdvoltagerepresentsthevoltageatwhichtheMOSFETstartstoturnon,whilstthemaximumgate-sourcevoltageisthemaximumgate-sourcevoltagethattheMOSFETcanwithstandsafely.WhatisanchannelMosfet?TheN-ChannelMOSFEThasanN-channelregionlocatedinbetweenthesourceanddrainterminals.Itisafour-terminaldevicehavingtheterminalsasgate,drain,source,body.InthistypeofFieldEffectTransistor,thedrainandsourceareheavilydopedn+regionandthesubstrateorbodyareofP-type.

75BUS

DescriptionThe2N7002isalogiclevelMOSFETwithalowon-stateresistance.Themosfethasalowgatetosourcethresholdvoltageof2.1Vtypicallythismakesthemosfetsuitableevenfor3.3Vapplicationcircuits.Sincethemosfethaslowonstateresistanceithashighefficiencyduringwhenthemosfetinon.Duetothispropertyitcanmaintainhighswitchingperformanceandhenceusedwidelyinpowermanagementapplications.ThemosfetalsocomesinaSMDpackagehencecanbeusedforcompactapplications.Oneconsiderabledisadvantageofthemosfetisitslowdraincurrent;itcanprovideacontinuouscurrentof200mAandpeakscurrentsupto1Aatmaximumthresholdvoltage.Anythingmorethanthatwilldamagethemosfet.CatalogDescriptionPinConfigurationFeaturesDucumentsandMediaPackageOutlineApplicationsAlternativesProductManufacturerOrdering&QuantityPinConfigurationPinNo.PinNameDescription1GateControlsthebiasingoftheMOSFET2SourceCurrentflowsoutthroughSource3DrainCurrentflowsinthroughDrainFeaturesSuitableforlogiclevelgatedrivesourcesSurface-mountedpackageVeryfastswitchingTrenchMOSFETtechnologyDocumentsandMediaDatasheet2N7002N-ChannellogiclevelMOSFETDatasheetPackageOutlineApplicationsLowcurrentandLowVoltageswitchingapplicationsDC-DCconverterseMobilityapplicationsApplicationwherelowon-stateresistanceisrequired.PowermanagementapplicationsAlternativesNTR4003,FDC666,FDC5582N7002EquivalentP-Channel:BSS84,FDN358POtherN-ChannelMOSFETs:BS170N,IRF3205,2N7000,IRF1010E,IRF540NProductManufacturerNXPSemiconductorsN.V.(NXP)isaholdingcompany.TheCompanyoperatesasasemiconductorcompany.TheCompanyprovideshighperformancemixedsignalandstandardproductsolutions.TheCompanyssegmentsareHighPerformanceMixedSignal(HPMS),StandardProducts(SP),andCorporateandOther.Itsproductsolutionsareusedinarangeofend-marketapplications,includingautomotive,personalsecurityandidentification,wirelessandwirelineinfrastructure,mobilecommunications,multi-marketindustrial,consumerandcomputing.Itengageswithglobaloriginalequipmentmanufacturers(OEMs)andsellsproductsinallgeographicregions.NXPsHPMSsegmentincludesbusinesslines,suchasAutomotive,SecureIdentificationSolutions(SIS),SecureConnectedDevices(SCD),andSecureInterfacesandInfrastructure(SII).TheCompanysSPsegmentsuppliesarangeofstandardsemiconductorcomponents,suchassmallsignaldiscretesandpowerdiscretes.DescriptionTheweatherinthepasttwodayshassuddenlycooleddown,andIforgottoinstallaswitchonthebedside,andIdontwanttogetoutofbedtoturnoffthelightbecauseofthecold.Atthistime,itwouldbenicetohaveanintelligentcontrolswitch.ThisblogintroducesasmartswitchcontrollerbasedonATMEGA328P-PU.Thecontroller,withoutchangingtheexistingswitchesandcircuits,canautomaticallyturnoffthelightsafterapowerfailure.Atthesametime,thewirelesscontrollightswitchfunctioncanalsoberealizedthroughtheBluetoothmodule,andthelightcanbeturnedonandoffwhilelyingdown,andthereisnoneedtogetoutofbed.ATMEGA328P-PUCatalogDescriptionIIntroductionIIATmega328P-PUBasedSystemPricipleIIIATmega328P-PUBasedSystemHardwareDesign3.1Centralcontrolmodule3.2Lightdetectioncircuit3.3BluetoothmoduleIVATmega328P-PUBasedStructureDesignVATmega328P-PUBasedSystemSoftwareDesignVIConclusionComponentDatasheetFAQOrdering&QuantityIIntroductionThesmartswitchlightcontrollerbasedonATmega328P-PUintroducedinthisblogconsistsofthefollowingmodules:LightDetectionModule:Perceivethechangeofindoorlightintensity;BluetoothModule:controlandrealizeautomaticlightswitch;SteeringGearandMechanicalLinkageMechanism:Itcanalsoautomaticallyturnoffthelights.Thecontrollerusestheorganiccombinationofmechatronics,whichisreliableandeasytocontrol.IIATmega328P-PUBasedSystemPricipleTheintelligentswitchlightcontrollersystemismainlycomposedoflightdetectionmodule,Bluetoothmodule,steeringgearandArduinocontrolsystem.Thesystemcontrolprocessisasfollows:Thelightdetectionmoduleperceivestheenvironmentfrombrighttodark;ThelightdetectionmodulesendsthesensedinformationtotheArduino;Arduinoturnsoffthelightingequipmentbycontrollingthesteeringgearaccordingtothisinformation;Or,tocompletetheoperationofturningoffthelights,youcanalsodirectlycontrolitthroughthemobilephoneAPPBluetooth.ThesystemprinciplediagramoftheintelligentswitchlightcontrollerisshowninFigure1.Figure1.SystemschematicdiagramIIIATmega328P-PUBasedSystemHardwareDesign3.1CentralcontrolmoduleThemostwidelyusedmicrocontrollersforthecentralcontrolmoduleareAVRand51microcontrollers.Fromtheperspectiveoffunctionandupgradepotential,theAVR8-bitmicrocontrollerATMEGA328P-PUwasselectedasthecentralcontrolmodule.So,whataretheadvantagesofATMEGA328P-PUcontrolmodule?Whychooseit?ATMEGA328P-PU,asacentralcontrolmodule,hasflexibleI/Oportresourcesandpowerfulfunctions.Itnotonlyhaslowpowerconsumptionbutisreliable,andcanmeettheneedsofsubsequentequipmentupdates.Figure2showstheminimumsystemdiagramofATMEGA328P.Figure2.ATMEGA328Pminimumsystem3.2LightdetectioncircuitHere,thelightdetectioncircuitisafour-wiresystem.TheAOportisananalogsignaloutputport,whichconvertstheexternallightintensityintoacontinuousoutputvoltagevalue.Whenthebrightnessofthelightchanges,howdoestheDOportactasadigitalsignaloutputport?Whentheambientlightbrightnessdoesnotreachthesetthreshold,theDOterminaloutputsahighlevel;Whenthebrightnessoftheambientlightexceedsthesetthreshold,theDOterminaloutputsalowlevel.Becausethesignaloutputbythecircuitisstableandreliable,thecontrollerselectsthedigitalsignaloutputbytheDOportastheinputsignalofthecontrolmodule.Inthisway,thesensitivityandreliabilityofthesystemcanbeimproved.IlluminationdetectioncircuitdiagramshowninFigure3.Figure3.Illuminationdetectioncircuitdiagram3.3BluetoothmoduleThisblogusestheHC-05master-slaveintegratedBluetoothmodule.ItscircuitdiagramisshownasinFig.4.Figure4.BluetoothdetectioncircuitThemoduleadoptsCSRmainstreamBluetoothchip,BluetoothV2.0protocolstandard,andcanworkwith3.3Vlowvoltage.Itischeap,smallinsize,stableinsignal,lowinpower,andcanbeusedinconjunctionwithmobileAPPtorealizewirelesscontrolofthesystem.Inthisdesign,Bluetoothonlyactsasaslave,receivinginstructionsfromthemobilephone.IVATmega328P-PUBasedStructureDesignTakethedormitoryasanexampletodesignthecontrollerfortheswitch(asshowninFigure5).Figure5.PowerswitchAftermeasurement,whentheswitchisintheequilibriumposition,thatis,betweentheclosedandopenpositions,ifthelight-offpositionispressedmorethan2mm,thebuttonwillturnoffthepower.Whenthelight-onpositionispresseddownmorethan2mm,thebuttonwillturnonthepower.Wecandesignalinkmechanismconnectedwiththesteeringgeartomake:Whenthesteeringgearrotatesto180,theconnectingrodpositionisthehighest;Whenthesteeringgearrotatesto0,theconnectingrodpositionislowest.Then,settheinitialpositionofthesteeringgearto90,sothatthebuttonisatthevalueofthebalanceposition.Atthistime,coincidethemiddlepositionoftheT-shapedfixingbracketwiththemiddlepositionofthebutton.Inaddition,inordertofacilitatetherealizationoffunctions,thecentralpositioncanbesetasachute.Figure6showsthedesignandinstallation.Figure7showsthatthecontrollerisdesignedasarectangularbox.Figure8showsthelayoutofeachmodule.Figure9showsthephysicalobjectandinstallationdiagramofthesmartswitchcontroller.Figure6.DesignandinstallationdrawingofconnectingrodpartFigure7.OverallviewofthecontrollerFigure8.SchematicdiagramofeachmoduleinstallationFigure9.PhysicalimageofsmartswitchcontrollerVATmega328P-PUBasedSystemSoftwareDesignThesoftwarepartcompletestheprocessingofthesignalsreceivedbythelightdetectionmoduleandtheBluetoothmodule,andthencontrolsthemechanicalstructuretoswitchthelights.Figure10showsthesystemsoftwareflowchart.Thelightdetectionmodule(theschematicdiagramofthelightdetectionmoduleisshowninFigure11)isusedtodetectchangesinbrightnessanddarknessofthesurroundingenvironment.Whenthesurroundingenvironmentisalwaysinalightstate,thelightdetectioncircuitwillcontinuouslysendalow-levelsignal0tothecentralcontrolmodule;Whenthesurroundingenvironmenthasbeeninadarkstate,thelightdetectioncircuitwillcontinuouslysendahighlevelsignal1tothecentralcontrolmodule.Whenthesurroundingenvironmentchangesfromnolighttolight(judgingthedaybreak),inthiscase,thesystemdoesnotact.Whenthesurroundingenvironmentchangesfromlighttonolight(judgedasamomentofpowerfailure),thelightdetectioncircuitwillstarttosendahighlevelsignal1tothecentralcontrolmodule.Atthemomentoftransition,thecentralcontrolmodulewillcontrolthesystemtoexecuteaworkcycle.Afterturningoffthelight,thesystemwillautomaticallyresetandwaitforthenextchangefromlighttonolight.Becausetheportmemoryofthecentralcontrolmoduleislimited,andthelightdetectioncircuitcontinuouslytransmitsdatatotheport.Thiswillcausethecentralcontrolmoduletorestartinashorttimeduetoexhaustionofmemory,makingthesystemunstableandunreliable.Therefore,aportclearingfunctionisspeciallywrittenwhencompilingthesystemtoensurethattheexpireddatasentbythelightdetectioncircuitisclearedintime.Therebyimprovingthestabilityandreliabilityofthesystem.Figure10.SystemsoftwareflowchartAftertalkingaboutthelightdetectionmodule,howdoestheBluetoothmoduleprocessthereceivedsignaltocontroltheswitch?WecanusemobilephoneAPPandBluetoothmoduletocontrolthesystemtoturnonandoffthelightsthroughwirelesstransmission.WhenthemobilephonesendsthecommandcharacterAtothecentralcontrolmodulethroughtheBluetoothmodule,thesystemwillexecuteacycleofturningoffthelights,andthenautomaticallyreset;Inthesameway,whenthemobilephonesendsthecommandcharacterBtothecentralcontrolmodulethroughtheBluetoothmodule,thesystemexecutesalight-oncommandforaworkingcycle,andthenautomaticallyresets.Figure11.SchematicdiagramofthelightmoduleVIConclusionThesmartswitchlightcontrollerdiscussedinthisbloghassignificantadvantages:*Donotchangethecircuitoftheoriginalpush-typepowerswitch.Therefore,itisnotonlysafe,butalsoeasytodisassembleandassemble;*TurnonandoffthelightsviaBluetoothwirelesscontrol.Therefore,ithasstrongoperability;*Aftercompletingtheswitchlampworkcycle,realizeautomaticreset.Inaddition,whilerealizingautomation,wecanalsomoveourfingerstoeasilyswitchlightsonthebed;*ATmega328P-PUhasgreatdevelopmentpotential.Thereasonforusingitistomeettheneedsofexpandingfunctionsinthefuture.suchas:CooperatewithWIFImodule:canrealizeultra-remotecontrol;Cooperatewithtimer:itcanrealizethefunctionofturningonthelightsatatime.Insummary,theintelligentswitchlightcontrollerbasedonATmega328P-PUweintroducedissimpleandreasonableinstructure,easytoinstall,safe,convenientandefficienttooperate.WiththesmartswitchlightcontrollerofATmega328P-PU,whenwelazilylieonthebedandplaywiththemobilephone,weusethemobilephonetocontrolthelightswitch.Atnight,weareafraidthatweforgettoturnoffthelightswhenwefallasleep,andwedontneedtogetoutofbed.Itcanalsoautomaticallyturnoffthelightswhenitgetsdark.ComponentDatasheetATMEGA328PDatasheetFAQWhatismeantbyATMEGA328P?ATMEGA328Pishighperformance,lowpowercontrollerfromMicrochip.ATMEGA328Pisan8-bitmicrocontrollerbasedonAVRRISCarchitecture.ItisthemostpopularofallAVRcontrollersasitisusedinARDUINOboards.WhatisthedifferencebetweenATMEGA328andATMEGA328P?ATMEGA328PandATMEGA328arethesameeverysensearchitecturally.ATMEGA328PjustconsumeslowerpowerthanATMEGA328,whichmeansthatthe328Pismanufacturedinafinerprocessthanthe328.WhyATMEGA328isusedinArduino?TheATMEGA328/Pisalow-powerCMOS8-bitmicrocontrollerbasedontheAVRenhancedRISC(reducedinstructionsetcomputer)architecture.InOrdertomaximizeperformanceandparallelism,theAVRusesHarvardarchitecturewithseparatememoriesandbusesforprogramanddata.HowdoyoucodeATMEGA328P?IsATMEGA328Pamicrocontroller?TheATMEGA328isasingle-chipmicrocontrollercreatedbyAtmelinthemegaAVRfamily(laterMicrochipTechnologyacquiredAtmelin2016).IthasamodifiedHarvardarchitecture8-bitRISCprocessorcore.CantheATMEGA328PmicrocontrollerbeusedwithouttheArduinoboard?Yes.YoucanuseATMega328Pwithoutarduinoboard....YoucanusearduinoboardwiththeIC.ProgramtheICandthentakeitoutanduseitinyourcircuit.Youwillhavetouse16MHZOscillatorwithcapacitors.HowdoIprogramAtmega328Pwithoutbootloader?ProgrammingAVRWithArduinoAsISPWithoutBootloaderandExternalCrystalStep1:ThingsYouNeed....Step2:UploadArduinoISPCodeonArduinoBoard....Step3:OpenCommandPrompt(inWindowsOS)...Step4:RequiredDownloads.....Step5:InstallationofWinAVR(onlyHelpforWindowsOSIsCoveredforNow)DescriptionTheCD405xBanalogmultiplexersanddemultiplexersaredigitally-controlledanalogswitcheshavinglowONimpedanceandverylowOFFleakagecurrent.ThesemultiplexercircuitsdissipateextremelylowquiescentpoweroverthefullVDDVSSandVDDVEEsupplyvoltageranges,independentofthelogicstateofthecontrolsignals.TheCD4051Bisasingle8-Channelmultiplexerhavingthreebinarycontrolinputs,A,B,andC,andaninhibitinput.Thethreebinarysignalsselect1of8channelstobeturnedon,andconnectoneofthe8inputstotheoutput.CatalogDescriptionPinoutConfigurationandFunctionCD4051BlockDiagramDocumentsandMediaFeaturesApplicationCD4051TypicalApplicationCircuitsOrdering&QuantityPinoutConfigurationandFunctionCD4051BlockDiagramThelogicdiagramofCD4051iscomposedofthreeparts:logiclevelconversioncircuit,8select1decodingcircuitand8CMOSswitchunits.A,BandCare3-bitbinaryaddressinputterminals,and8combinationsof3-bitbinarycanbeusedforselection8channels;INHistheaddressinputprohibitionterminal,whenitishigh,theaddressinputterminalisinvalid,thatis,nochannelisstrobed.TheinputlevelsofA,B,CandINHarecompatiblewithTTL.CD4051has8input\outputterminals,1output/inputterminal,digitalcircuitpowersupply+Eand-E1,analogcircuitpowersupply+Eand-E2.ThemainfunctionofthelogiclevelconversioncircuitistoinputtheaddressA,B,CandaddressinputinhibitterminalINHinputTTLlogiclevelisconvertedintoCMOSlevel,sothattheswitchunitcanbecontrolledbyTTLlevel.Themainfunctionofthe8-to-1addressdecodingcircuitistoconverttheaddressinputsignalfromthelogiclevelconversioncircuitintothecorrespondingswitchunitstrobesignalandturnonthecorrespondingswitchunit.DocumentsandMediaDatasheetCD405xBCMOSSingle8-ChannelAnalogMultiplexer/DemultiplexerwithLogic-LevelConversiondatasheet(Rev.I)FeaturesWideRangeofDigitalandAnalogSignalLevelsDigital:3Vto20VAnalog:20VP-PLowONResistance,125Ω(Typical)Over15VP-PSignalInputRangeforVDDVEE=18VHighOFFResistance,ChannelLeakageof100pA(Typical)atVDDVEE=18VLogic-LevelConversionforDigitalAddressingSignalsof3Vto20V(VDDVSS=3Vto20V)toSwitchAnalogSignalsto20VP-P(VDDVEE=20V)MatchedSwitchCharacteristics,rON=5Ω(Typical)forVDDVEE=15VVeryLowQuiescentPowerDissipationUnderAllDigital-ControlInputandSupplyConditions,0.2W(Typical)atVDDVSS=VDDVEE=10VBinaryAddressDecodingonChip5V,10V,and15VParametricRatings100%TestedforQuiescentCurrentat20VMaximumInputCurrentof1Aat18VOverFullPackageTemperatureRange,100nAat18Vand25CBreak-Before-MakeSwitchingEliminatesChannelOverlapApplicationAnalogandDigitalMultiplexingandDemultiplexingA/DandD/AConversionSignalGatingFactoryAutomationTelevisionsAppliancesConsumerAudioProgrammableLogicCircuitsSensorsCD4051TypicalApplicationCircuits1.CD4051,CH3130multi-channeldemodulatorcircuitdiagramThiscircuitismainlycomposedof8-channelanalogswitchCD4051andvoltagefollowerCH3130,etc.TheinputsignaloftheprohibitionterminalINHofanalogswitchCD4051isusedtocontrolthegatingofvoltagefollowerCH3130,therebyperformdemodulationtomultipleanalogsignals.2.CD4051constructs32-channelcircuitBecausetheCD4051hasonlyeightinputports,fourCD4051sareneededtobuilda32-waymultiplexer,labeledINH1,INH2,INH3,andINH4.The32-waymultiplexershouldhave5controlports,ofwhichthefirstthreearetheinputportsofCD4051andthelasttwoarecontrolports.(BecauseCD4051hasthreeinputports),labelthemasD1,D2,D3,D4,D5(0000011111,00000channel0,11111channel31).Thebasicideaistorealizethechoiceof32channelports(0-7,8-15,16-23,24-31)byselecting4CD4051s.IfyouchoosethethirdCD4051,youcanchoose16-23(10000-10111)channelport.However,theselectionofCD4051isachievedbycontrollingtheINHlevelofeachCD4051.Forexample,ifyouwanttoturnonthethirdCD4051,makeitsINHhigh(atthistimeD5=1,D4=0,thenINH3=D5!D4).Therefore,thechoiceofINHisachievedbycontrollingthelogicalrelationshipbetweenD5andD4.WhereINH1=!D5!D4;INH2=!D5D4;INH3=D5!D4;INH4=D5D4.

75BUS

DescriptionLM317isaadjustable3-terminalpositive-voltageregulator,thisbolgcoversLM317regulatoralternative,datasheet,applications,featuresandotherinformationonhowtouseandwheretousethisdevice.ABasicIntroductiontoLM317VoltageRegulatorCatalogDescriptionLM317PinoutLM317FeaturesLM317ApplicationsLM317CircuitLM317ParametersLM317CADModelLM317AdvantageLM317ElectricalCharacteristicsLM317PackageLM317AlternativesLM317EquivalentsWheretouseLM317HowtouseLM317LM317ManufacturerComponentDatasheetFAQOrdering&QuantityLM317PinoutPinNumberPinNameDescription1AdjustThispinsadjuststheoutputvoltage2OutputVoltage(Vout)Theregulatedoutputvoltagesetbytheadjustpincanbeobtainedfromthispin3InputVoltage(Vin)TheinputvoltagewhichhastoberegulatedisgiventothispinLM317FeaturesOutputvoltagerangeadjustablefrom1.25Vto37VOutputcurrentgreaterthan1.5AInternalshort-circuitcurrentlimitingThermaloverloadprotectionOutputsafe-areacompensationLM317ApplicationsATCAsolutionsDLP:3Dbiometrics,hyperspectralimaging,opticalnetworking,andspectroscopyDVRandDVSDesktopPCsDigitalsignageandstillcamerasECGelectrocardiogramsEVHEVchargers:levels1,2,and3ElectronicshelflabelsEnergyharvestingEthernetswitchesFemtobasestationsFingerprintandirisbiometricsHVAC:heating,ventilating,andairconditioningHigh-speeddataacquisitionandgenerationHydraulicvalvesIPphones:wiredandwirelessIntelligentoccupancysensingMotorcontrols:brushedDC,brushlessDC,lowvoltage,permanentmagnet,andsteppermotorsPoint-to-pointmicrowavebackhaulsPowerbanksolutionsPowerlinecommunicationmodemsPoweroverethernet(PoE)PowerqualitymetersPowersubstationcontrolsPrivatebranchexchanges(PBX)ProgrammablelogiccontrollersRFIDreadersRefrigeratorsSignalorwaveformgeneratorsSoftware-definedradios(SDR)Washingmachines:high-endandlow-endX-rays:baggagescanners,medical,anddentalLM317CircuitLM317ParametersOutputoptionsAdjustableOutputIout(Max)(A)1.5Vin(Max)(V)40Vin(Min)(V)3Vout(Max)(V)37Vout(Min)(V)1.25Noise(uVrms)38Iq(Typ)(mA)5ThermalresistanceJA(C/W)24Approx.price(US$)1ku|0.14Loadcapacitance(Min)(F)0RatingCatalogRegulatedoutputs(#)1FeaturesAccuracy(%)5PSRR@100KHz(dB)38Dropoutvoltage(Vdo)(Typ)(mV)2000Operatingtemperaturerange(C)0to125IhsManufacturerTEXASINSTRUMENTSINCBrandNameTexasInstrumentsLM317CADModelPackagePinsDownloadDDPAK/TO-263(KTT)3ViewoptionsSOT-223(DCY)4ViewoptionsTO-220(KCS)3ViewoptionsTO-220(KCT)3ViewoptionsLM317ElectricalCharacteristicsOverrecommendedrangesofoperatingvitualjunctiontemperature(unlessotherwisenoted)LM317PackageDDPAK/TO-263(KTT)SOT-223(DCY)TO-220(KCS)TO-220(KCT)LM317AlternativesSharethesamefunctionalityandpinoutbutisnotanequivalenttothecompareddevice:LM7805,LM7806,LM7809,LM7812,LM7905,LM7912,LM117V33,XC6206P332MR.LM317EquivalentsLT1086,LM1117(SMD),PB137,LM337(NegativeVariableVoltageregulator)WheretouseLM317WhenitcomestovariablevoltageregulationrequirementsLM317wouldmostlikelybethefirstchoice.Apartfromusingitasavariablevoltageregulator,itcanalsobeusedasafixedvoltageregulator,currentlimiter,Batterycharger,ACvoltageregulatorandevenasanadjustablecurrentregulator.OnenotabledrawbackofthisICisthatithasavoltagedropofabout2.5acrossitduringregulation,soifyoulookingtoavoidthatproblemlookintotheotherequivalentICsgivenabove.So,ifyouarelookingforavariablevoltageregulatortodelivercurrentupto1.5AthenthisregulatorICmightbetherightchoiceforyourapplication.HowtouseLM317LM317isa3-terminalregulatorICanditisverysimpletouse.Ithasmanyapplicationcircuitsinitsdatasheet,butthisICisknownforbeingusedasavariablevoltageregulator.So,letslookintohowtousethisICasavariablevoltageregulator.AssaidearliertheIChas3pins,inwhichtheinputvoltageissuppliedtopin3(VIN)thenusingapairofresistors(potentialdivider)wesetavoltageatpin1(Adjust)whichwilldecidetheoutputvoltageoftheICthatisgivenoutatpin2(VOUT).Nowtomakeitactasavariablevoltageregulatorwehavetosetvariablevoltagesatpin1whichcanbedonebyusingapotentiometerinthepotentialdivider.Thebelowcircuitisdesignedtotake12V(youcansupplyupto24V)asinputandregulateitfrom1.25Vto10V.TheResistorR1(1K)andthepotentiometer(10k)togethercreatesapotentialdifferenceatadjustpinwhichregulatestheoutputpinaccordingly.TheformulaetocalculatetheOutputvoltagebasedonthevalueofresistorsisVOUT=1.25(1+(R2/R1))Now,letsverifythisformulafortheabovecircuit.ThevalueofR1is1000ohmsandthevalueofR2(potentiometer)is5000becauseitisa10kpotentiometerplacedat50%(50/100of1000is5000).Vout=1.25(1+(5000/1000))=1.256=7.5VAndthesimulationshows7.7Vwhichisprettymuchclose.Youcanvarytheoutputvoltagebysimplyvaryingthepotentiometer.Inourcircuit,amotorisconnectedasaloadwhichconsumesaround650mAyoucanconnectanyloadupto1.5A.Thesameformulaecanalsobeusedtocalculatethevalueofresistorforyourequiredoutputvoltage.Oneeasywaytodothisistousethisonlinecalculatortorandomlysubstitutethevalueofresistorsyouhaveandcheckwhichoutputvoltageyouwillget.LM317ManufacturerTexasInstrumentsInc.(TI)isanAmericantechnologycompanythatdesignsandmanufacturessemiconductorsandvariousintegratedcircuits,whichitsellstoelectronicsdesignersandmanufacturersglobally.ItsheadquartersareinDallas,Texas,UnitedStates.TIisoneofthetoptensemiconductorcompaniesworldwide,basedonsalesvolume.TexasInstrumentssfocusisondevelopinganalogchipsandembeddedprocessors,whichaccountsformorethan80%oftheirrevenue.TIalsoproducesTIdigitallightprocessing(DLP)technologyandeducationtechnologyproductsincludingcalculators,microcontrollersandmulti-coreprocessors.Todate,TIhasmorethan43,000patentsworldwide.ComponentDatasheetLM317DatasheetFAQWhatislm317usedfor?TheLM317servesawidevarietyofapplicationsincludinglocal,oncardregulation.Thisdevicecanalsobeusedtomakeaprogrammableoutputregulator,orbyconnectingafixedresistorbetweentheadjustmentandoutput,theLM317canbeusedasaprecisioncurrentregulator.Whatisthemaximuminputvoltageoflm317?TheLM317isanadjustablevoltagelinearregulatorthatcanoutput1.2537Vatupto1.5Acurrentwithaninputvoltagerangeof340V.Whatisthedifferencebetweenlm317andlm317t?Member.Thereisnofunctionaldifferenceastheyareoneinthesame.TheTattheendjustindicatesthatitsinaTO-220package.Theyusuallytagonextrathingsafterthepartnametoreferencethingslikepackage,temprange,etc.Islm317atransistor?TheLM317isanadjustablethree-terminalpositive-voltageregulatorcapableofsupplyingmorethan1.5Aoveranoutput-voltagerangeof1.25Vto32V....Byusingaheat-sinkedpasstransistorsuchasa2N3055(Q1)wecanproduceseveralampsofcurrentfarabovethe1.5ampsoftheLM317.Howdoesanlm317work?Thecircuitconsistsofalow-sideresistorandhigh-sideresistorconnectedinseriesformingaresistivevoltagedividerwhichisapassivelinearcircuitusedtoproduceanoutputvoltagewhichisafractionofitsinputvoltage.WhatisIClm317?TheLM317deviceisanadjustablethree-terminalpositive-voltageregulatorcapableofsupplyingmorethan1.5Aoveranoutput-voltagerangeof1.25Vto37V.Itrequiresonlytwoexternalresistorstosettheoutputvoltage.Thedevicefeaturesatypicallineregulationof0.01%andtypicalloadregulationof0.1%.HowdoIknowifmylm317isworking?Testinglm317t.Ifyoulooktotheic,thelegstowardsyou,therightoneistheinputpin.youmustseeadifferenceofminimum1.2Vbetweenthetwopins,otherwisetheICisfaulty.furthermore,thefirsttestistoseeifyouhaveinputvoltage!Whatistheworkingpricipleoflm317?LM317worksonaverysimpleprinciple.Itisavariablevoltageregulatori.e.supportsdifferentoutputvoltagelevelsforaconstantappliedinputvoltagesupply.HowtomakeasimplevoltageregulatorcircuitusingLM317?DescriptionLM339(Quaddifferentialcomparator)consistoffourindependentvoltagecomparators.Itisacommonintegratedcircuitandismainlyusedinhigh-voltagedigitallogicgatecircuits.UsingLM339caneasilyformvariousvoltagecomparatorcircuitsandoscillatorcircuits.CatalogDescriptionComponentDatasheetLM339PinoutBasicParametersFeaturesApplicationPinFunctionListCircuitDiagramPackageElectricalCharacteristicsInstructionsProductManufacturerFAQOrdering&QuantityComponentDatasheetComparatorDatasheetLM339DatasheetLM339PinoutLM339PinoutBasicParametersParameternameSymbolNumericalvalueunitsupplyvoltageVCC18or36VDifferentialmodeinputvoltageVID36VCommonmodeinputvoltageVI-0.3~VCCVPowerdissipationPd570mWWorkingenvironmenttemperatureTopr0to+70℃StoragetemperatureTstg-65to150℃FeaturesLowvoltageoffset,generally2mVThecommon-modevoltagerangeisverylarge,from0vtothepowersupplyvoltageminus1.5vTheinternalresistancelimittothesignalsourceisverywideSingleSupplyOperation:2-36VDualSupplyOperation:1V-18VThepotentialofoutputcanbeselectedflexiblyandconvenientlyLM339issimilartooperationalamplifierwithnon-adjustablegain.Eachcomparatorhastwoinputsandoneoutput.Oneofthetwoinputterminalsiscalledthenon-invertinginputterminal,whichisrepresentedby+,andtheotheriscalledtheinvertinginputterminal,whichisrepresentedby-.Whencomparingtwovoltages,addafixedvoltageasareferencevoltageatanyinputterminal,andaddasignalvoltagetobecomparedattheotherterminal.Whenthevoltageatthe+terminalishigherthanthe-terminal,theoutputtubewillcutoff.Whenthevoltageofthe-terminalishigherthanthe+terminal,theoutputtubeissaturated.Thevoltagedifferencebetweenthetwoinputterminalsisgreaterthan10mV,whichcanensurethattheoutputcanbereliablyswitchedfromonestatetoanotherstate.Therefore,itisidealtousetheLM339inweaksignaloccasions.TheoutputterminalofLM339isequivalenttoacrystaltransistorthatisnotconnectedtothecollectorresistor.Whenusing,theoutputterminaltothepositivepowersupplygenerallyneedstobeconnectedtoaresistor(calledpull-upresistor).Choosingpull-upresistorswithdifferentresistancevalueswillaffectthevalueofthehighpotentialattheoutput.Becausewhentheoutputtransistorisoff,itscollectorvoltagebasicallydependsonthevalueofthepull-upresistorandtheload.Inaddition,theoutputofeachcomparatorisallowedtobeconnectedtogether.ApplicationIndustrialAutomotiveInfotainmentandClustersBodyControlModulePowerSupervisionOscillatorsPeakDetectorsLogicVoltageTranslationPinFunctionListPinNumberPinfunctionSymbolPinNumberPinfunctionSymbol1Output2OUT28Invertinginput31N-(3)2Output1OUT19Forwardinput31N+(3)3PowerSupplyVCC+10Invertinginput41N-(4)4Invertinginput11N-(1)11Forwardinput41N+(4)5Positiveinput11N+(1)12PowerSupplyVcc6Invertinginput21N-(2)13Output4OUT47Forwardinput2OUT2(2)14Output3OUT3CircuitDiagramLM339CircuitDiagramPackageLM339PackageElectricalCharacteristicsVCC=5.0V,Tamb=25℃,unlessotherwisestatedParameternameSymbolTestconditionsMinimumTypicalMaximumunitInputoffsetvoltageVIOVCM=0toVCC-1.5VO(P)=1.4V,Rs=0-1.05.0mVInputoffsetcurrentIIO--550nAInputbiascurrentIb--65250nACommonmodeinputvoltageVIC-0-VCC-1.5VQuiescentCurrentICCVCC=+5V,noload-1.12.0mAVCC=+30V,noload-1.32.5mAVoltagegainAVVCC=15V,RL>15k-200-V/mVSinkcurrentIsinkVi(-)>1V,Vi(+)=0V,Vo(p)<1.5V616-mAOutputleakagecurrentIOLEVi(-)=0V,Vi(+)=1V,VO=5V-0.1-nAInstructionsTheLM339seriesarehighgain,widebandwidthdeviceswhich,likemostcomparators,caneasilyoscillateiftheoutputleadisinadvertentlyallowedtocapacitivelycoupletotheinputsviastraycapacitance.Thisshowsuponlyduringtheoutputvoltagetransitionintervalsasthecomparatorchangesstates.Powersupplybypassingisnotrequiredtosolvethisproblem.StandardPCboardlayoutishelpfulasitreducesstrayinput-outputcoupling.Reducingthisinputresistorsto10kreducesthefeedbacksignallevelsandfinally,addingevenasmallamount(1to10mv)ofpositivefeedback(hysteresis)causessucharapidtransitionthatoscillationsduetostrayfeedbackarenotpossible.SimplysocketingtheICandattachingresistorstothepinswillcauseinput-outputoscillationsduringthesmalltransitionintervalsunlesshysteresisisused.Iftheinputsignalisapulsewaveform,withrelativelyfastriseandfalltimes,hysteresisisnotrequired.Allpinsofanyunusedcomparatorsshouldbetiedtothenegativesupply.ThebiasnetworkofLM339establishesadraincurrentwhichisindependentofthemagnitudeofthepowersupplyvoltageovertherangeoffrom2Vto30V.Itisusuallyunnecessarytouseabypasscapacitoracrossthepowersupplyline.ThedifferentialinputvoltagemaybelargerthanV+withoutdamagingthedevice.Protectionshouldbeprovidedtopreventtheinputvoltagesfromgoingnegativemorethan-0.3VDC(at25℃).Aninputclampdiodecanbeusedasshownintheapplicationssection.TheoutputoftheLM339istheuncommittedcollectorofagrounded-emitterNPNoutputtransistor.ManycollectorscanbetiedtogethertoprovideanoutputORingfunction.Anoutputpull-upresistorcanbeconnectedtoanyavailablepowersupplyvoltagewithinthepermittedsupplyvoltagerangeandthereisnorestrictiononthisvoltageduetothemagnitudeofthevoltagewhichisappliedtotheV+terminaloftheLM1339package.TheoutputcanalsobeusedasasimpleSPSTswitchtoground(whenapull-upresistorisnotused).Theamountofcurrentwhichtheoutputdevicecansinkislimitedbythedriveavailable(whichisindependentofV+)andtheofthisdevice.Whenthemaximumcurrentlimitisreached(approximately16mA),theoutputtransistorwillcomeoutofsaturationandtheoutputvoltagewillriseveryrapidly.Theoutputsaturationvoltageislimitedbytheapproximately60RSAToftheoutputtransistor.Thelowoffsetvoltageoftheoutputtransistor(1mV)allowstheoutputtoclampessentiallytogroundlevelforsmallloadcurrents.ProductManufacturerTexasInstrumentsInc.(TI)isanAmericantechnologycompanythatdesignsandmanufacturessemiconductorsandvariousintegratedcircuits,whichitsellstoelectronicsdesignersandmanufacturersglobally.ItsheadquartersareinDallas,Texas,UnitedStates.TIisoneofthetoptensemiconductorcompaniesworldwide,basedonsalesvolume.TexasInstrumentssfocusisondevelopinganalogchipsandembeddedprocessors,whichaccountsformorethan80%oftheirrevenue.TIalsoproducesTIdigitallightprocessing(DLP)technologyandeducationtechnologyproductsincludingcalculators,microcontrollersandmulti-coreprocessors.Todate,TIhasmorethan43,000patentsworldwide.FAQWhatisLM339?LM339isavoltagecomparatorICfromLMx39xseriesandismanufacturedbymanyindustries.Thedevicesconsistoffourindependentvoltagecomparatorsthataredesignedtooperatefromasinglepowersupply.WhatisthedifferencebetweenLM324andLM339?TheLM324hasacomplementaryoutputwhiletheLM339isopencollector.Inthecomplementaryoutput,currentcanflowineitherdirectionasrequired(eithersourceorsink)whiletheopencollectoroutputcanonlysinkcurrent.HowdoesLM339comparatorwork?TheLM339isaquadopampcomparator.Acomparatorworksbyasimpleconcept.Eachopampofacomparatorhas2inputs,ainvertinginputandanoninvertinginput.Iftheinvertinginputvoltageisgreaterthanthenoninvertinginput,thentheoutputisdrawntoground.Whatiscomparatoric?Acomparatorisanelectroniccircuit,whichcomparesthetwoinputsthatareappliedtoitandproducesanoutput.Theoutputvalueofthecomparatorindicateswhichoftheinputsisgreaterorlesser.Pleasenotethatcomparatorfallsundernon-linearapplicationsofICs.WhatisthereplacementforLM339?LM311,LM324,LM397,LM139,LM239,LM2901Whatisacomparatorcircuit?Acomparatorcircuitcomparestwovoltagesandoutputseithera1(thevoltageattheplusside;VDDintheillustration)ora0(thevoltageatthenegativeside)toindicatewhichislarger.Comparatorsareoftenused,forexample,tocheckwhetheraninputhasreachedsomepredeterminedvalue.WhatistheuseofLM339?LM339isusedinapplicationswhereacomparisonbetweentwovoltagesignalsisrequired.Inadditionwithfourofthosecomparatorsonboardthedevicecancomparefourpairsofvoltagesignalsatatimewhichcomesinhandyinsomeapplications.

75BUS

DescriptionThe74HC595isanhighspeedCMOS8-BITSHIFTREGISTERS/OUTPUTLATCHES(3-STATE)fabricatedwithsilicongateC2MOStechnology.Thisdevicecontainsan8-bitserial-in,parallel-outshiftregisterthatfeedsan8-bitD-typestorageregister.Thestorageregisterhas83-STATEoutputs.Separateclocksareprovidedforboththeshiftregisterandthestorageregister.Theshiftregisterhasadirect-overridingclear,serialinput,andserialoutput(standard)pinsforcascading.Boththeshiftregisterandstorageregisterusepositive-edgetriggeredclocks.Ifbothclocksareconnectedtogether,theshiftregisterstatewillalwaysbeoneclockpulseaheadofthestorageregister.Allinputsareequippedwithprotectioncircuitsagainststaticdischargeandtransientexcessvoltage.TheShiftRegister:Explained[74HC595]CatalogDescriptionFeaturesApplicationPinoutLogicDiagramParametersComponentDatasheetPackageProductManufacturerFAQOrdering&QuantityFeaturesLowquiescentcurrent:80AmaximumLowinputcurrent:1Amaximum8-bitserial-in,parallel-outshiftregisterwithstorageWideoperatingvoltagerange:2V~6VShiftregisterhasdirectclearGuaranteedshiftfrequency:DCto30MHzPackage:SOP16ApplicationSerial-to-paralleldataconversionRemotecontrolholdingregisterPinoutPinNo.SymbolNameandFunction1,2,3,4,5,6,7,15QAtoQHDataoutput8GNDGround(0V)9QHSerialdataoutput10SCLRShiftregisterclearinput11SCKShiftregisterclockinput12RCKStorageregisterclockinput13GOutputenableinput14SISerialdatainput16VCCPositivesupplyvoltageLogicDiagramParametersBrandNameDiodesLow-powerconsumptionWhenTA=25℃,Icc=4A(MAX)LowquiescentcurrentMaximum80ALowinputcurrentMaximum1AWideoperatingvoltagerange2V-6VPackageDIP16/SOP16ComponentDatasheetDatasheet74HC595DatasheetPackageProductManufacturerDiodesIncorporatedisaleadingglobalmanufacturerandsupplierofhigh-qualityapplicationspecificstandardproductswithinthebroaddiscrete,logic,analog,andmixed-signalsemiconductormarkets.DiodescorporateheadquartersandAmericassalesofficearelocatedinPlano,Texas,andMilpitas,California.Diodesservetheconsumerelectronics,computing,communications,industrial,andautomotivemarkets.Diodesproductsincludediodes,rectifiers,transistors,MOSFETs,protectiondevices,function-specificarrays,singlegatelogic,amplifiersandcomparators,Hall-effectandtemperaturesensors,powermanagementdevices,includingLEDdrivers,AC-DCconvertersandcontrollers,DC-DCswitchingandlinearvoltageregulators,andvoltagereferencesalongwithspecialfunctiondevices,suchasUSBpowerswitches,loadswitches,voltagesupervisors,andmotorcontrollers.FAQWhatis74HC595?74HC595isashiftregisterwhichworksonSerialINParallelOUTprotocol.Itreceivesdataseriallyfromthemicrocontrollerandthensendsoutthisdatathroughparallelpins.Wecanincreaseouroutputpinsby8usingthesinglechip.Whatisa74hc595n?8-bitShiftRegister74HC595NAshiftregisterisachipyoucanusetocontrolmanyoutputs(8here)atthesametimewhileonlyusingafewpins(3here)ofyourArduino.Howdoesashiftregisterwork?Shiftregistersholdthedataintheirmemorywhichismovedorshiftedtotheirrequiredpositionsoneachclockpulse.Eachclockpulseshiftsthecontentsoftheregisteronebitpositiontoeithertheleftortheright.How74HC595ShiftRegiesterworks?The595hastworegisters(whichcanbethoughtofasmemorycontainers),eachwithjust8bitsofdata.ThefirstoneiscalledtheShiftRegister.TheShiftRegisterliesdeepwithintheICcircuits,quietlyacceptinginput.Howdoesan8bitshiftregisterwork?TheSN74HC595Nisasimple8-bitshiftregisterIC.Simplyput,thisshiftregisterisadevicethatallowsadditionalinputsoroutputstobeaddedtoamicrocontrollerbyconvertingdatabetweenparallelandserialformats.YourchosenmicroprocessorisabletocommunicatewiththeTheSN74HC595Nusingserialinformationthengathersoroutputsinformationinaparallel(multi-pin)format.Essentiallyittakes8bitsfromtheserialinputandthenoutputsthemto8pins.

DescriptionTheMMBT3904LT1GisaNPNsiliconBipolarTransistor,designedforuseinlinear,lowerpowersurfacemountandswitchingapplications.MMBT3904LT1GHowdoesatransistorwork?CatalogMMBT3904LT1GDescriptionMMBT3904LT1GPinoutMMBT3904LT1GFeaturesMMBT3904LT1GMarkingDiagramMMBT3904LT1GCADModelsMMBT3904LT1GFunctionalEquivalentsMMBT3904LT1GPackageOutlinesMMBT3904LT1GPopularitybyRegionMMBT3904LT1GMarketingPriceAnalysisMMBT3904LT1GManufacturerComponentDatasheetFAQOrdering&QuantityMMBT3904LT1GPinoutMMBT3904LT1GFeaturesTheseDevicesarePbFree,HalogenFree/BFRFreeandareRoHSCompliantSPrefixforAutomotiveandOtherApplicationsRequiringUniqueSiteandControlChangeRequirements;AECQ101QualifiedandPPAPCapableMMBT3904LT1GMarkingDiagramMMBT3904LT1GCADModelsPartSymbolFootprint3DModelMMBT3904LT1GFunctionalEquivalentsMMBT3904LT1GPackageOutlinesMMBT3904LT1GPopularitybyRegionMMBT3904LT1GMarketingPriceAnalysisMMBT3904LT1GManufacturerONSemiconductor(Nasdaq:ON)isdrivingenergyefficientinnovations,empoweringcustomerstoreduceglobalenergyuse.Thecompanyoffersacomprehensiveportfolioofenergyefficientpowerandsignalmanagement,logic,discreteandcustomsolutionstohelpdesignengineerssolvetheiruniquedesignchallengesinautomotive,communications,computing,consumer,industrial,LEDlighting,medical,military/aerospaceandpowersupplyapplications.ONSemiconductoroperatesaresponsive,reliable,world-classsupplychainandqualityprogram,andanetworkofmanufacturingfacilities,salesofficesanddesigncentersinkeymarketsthroughoutNorthAmerica,Europe,andtheAsiaPacificregions.ComponentDatasheetMMBT3904LT1GDatasheetFAQWhatisMMBT3904LT1G?TheMMBT3904LT1GisaNPNsiliconBipolarTransistor,designedforuseinlinear,lowerpowersurfacemountandswitchingapplications.Whatisatransistor?Atransistorisasemiconductordeviceusedtoamplifyorswitchelectronicsignalsandelectricalpower.Itiscomposedofsemiconductormaterialusuallywithatleastthreeterminalsforconnectiontoanexternalcircuit.WhatisPNPtransistor?APNPtransistorisabipolarjunctiontransistorconstructedbysandwichinganN-typesemiconductorbetweentwoP-typesemiconductors.APNPtransistorhasthreeterminalsaCollector(C),Emitter(E)andBase(B).ThePNPtransistorbehavesliketwoPNjunctionsdiodesconnectedbacktoback.Whatdoesatransistordo?Atransistor,alsoknownasaBJT(BipolarJunctionTransistor),isacurrentdrivensemiconductordevicewhichcanbeusedtocontroltheflowofelectriccurrentinwhichasmallamountofcurrentintheBaseleadcontrolsalargercurrentbetweentheCollectorandEmitter.Howmanytypesoftransistorarethere?Transistorsarebasicallyclassifiedintotwotypes;theyareBipolarJunctionTransistors(BJT)andFieldEffectTransistors(FET).TheBJTsareagainclassifiedintoNPNandPNPtransistors.TheFETtransistorsareclassifiedintoJFETandMOSFET.Whatistransistordiagram?DiagramAshowsanNPNtransistorwhichisoftenusedasatypeofswitch.Asmallcurrentorvoltageatthebaseallowsalargervoltagetoflowthroughtheothertwoleads(fromthecollectortotheemitter).ThecircuitshownindiagramBisbasedonanNPNtransistor.Whentheswitchispressedacurrentpassesthroughtheresistorintothebaseofthetransistor.Thetransistorthenallowscurrenttoflowfromthe+9voltstothe0vs,andthelampcomeson.Thetransistorhastoreceiveavoltageatitsbaseanduntilthishappensthelampdoesnotlight.Whatarethetwomainappilcationsoftransistor?Transistorsarecommonlyusedindigitalcircuitsaselectronicswitcheswhichcanbeeitherinanonoroffstate,bothforhigh-powerapplicationssuchasswitched-modepowersuppliesandforlow-powerapplicationssuchaslogicgates.IntroductionTheLM741seriesaregeneral-purposeoperationalamplifiers.Itisintendedforawiderangeofanalogueapplications.Thehighgainandwiderangeofoperatingvoltageprovidesuperiorperformanceinintegrator,summingamplifier,andgeneralfeedbackapplications.ThisarticlewillintroducethecircuitofcapacitancemeasurementcomposedofLM741.CatalogIntroductionCatalogICircuitDesignFAQOrdering&QuantityICircuitDesignAsFigure1shows,themeasuringprincipleofthiscircuitis:atriangularwaveisformedfromtheprocessofcharginganddischargingofmeasuredcapacitorCx.Andthecapacitancecanbemeasuredbytheoscillationperiodofthetriangularwave.AMillerintegratingcircuitconsistsofA1.ASchmidtcircuitconsistsofA2andtheSchmidtcircuitformspositivefeedbackandgeneratesoscillation.ItsamplitudeisdeterminedbyR4andR3,equalto1/3ofthesupplyvoltage.ThechargingcurrentofCxisdeterminedbythesupplyvoltageandR2,andthedischargecurrentisdeterminedbythesupplyvoltageandR1+R2.Inprinciple,theoscillationperiodshouldnotbeaffectedbythesupplyvoltage.However,duetothelimitationofA2differentialinputvoltageandtheconstantoftransistordrivingcircuit,itisnotallowedtochangethesupplyvoltagegreatly.Therangeofpowersupplyvoltageis13to15V.Theabsolutevaluesofpositiveandnegativesupplyvoltagesneedtobeequal.WhenthecapacitorCxisnotconnected,A2oscillateswithadelayofabout20S,andCxcanbecalculatedtocompensateforthis.Themeasurementtimeis10SwhentheCxcapacitanceis1000F.IfR1andR2use1Kresistance,themeasurementtimecanbeshortenedto1/10.CircuitoutputU.Thecapacitancecanbereadoutbyconnectingaexternalcounter.Figure1.capacitancemeasurementcircuitLM709formsapositivefeedbackthroughR7andVT2tothenegativeinputtoformaSchmidttrigger.WhenLM709outputsahighlevel,VT2issaturatedandturnedon,andthevoltageofCpoleofVT2is0V.BothVT3andVT1arecutoff.The+15VpowersupplychargesCxthroughR1andR2,andtheoutputvoltageoftheLM741graduallydecreases.Whenitdropsto0V,Schmidtreversesandtheoutputvoltagegoeslow(-15V).Atthistime,VT2iscutoff,andthevoltageofCpoleofVT2risesto+5V,consolidatingthelow-leveloutputstateofLM709.Atthesametime,VT3andVT1getthebasecurrentandturnon.TheCXisreverselychargedviaR2and-15Vpowersupplies.TheoutputvoltageofLM741increasesgradually.Whenitrisesto+5V,Schmidtreversesagainandtheoutputbecomeshighlevel.Thenacyclecomplete.Theaboveprocessisrepeatedtoformperiodicoscillations.FAQWhatislm741opamp?AnLM741operationalamplifierisaDC-coupledhighgainelectronicvoltageamplifier.Ithasonlyoneop-ampinside.AnoperationalamplifierICisusedasacomparatorwhichcomparesthetwosignal,theinvertingandnon-invertingsignal.WhyOpampiscalled741?The741OpAmpICisamonolithicintegratedcircuit,comprisingofageneralpurposeOperationalAmplifier.ItwasfirstmanufacturedbyFairchildsemiconductorsintheyear1963.Thenumber741indicatesthatthisoperationalamplifierIChas7functionalpins,4pinscapableoftakinginputand1outputpin.Howdoesa741opampwork?ThemostcommonOp-Ampisthe741anditisusedinmanycircuits.TheOPAMPisaLinearAmplifierwithanamazingvarietyofuses.Itsmainpurposeistoamplify(increase)aweaksignal-alittlelikeaDarlingtonPair.TheOP-AMPhastwoinputs,INVERTING(-)andNON-INVERTING(+),andoneoutputatpin6.Howdoyoucalculatelm386gain?VoltageGainAnalysis:Withoutanyexternalcomponents,ithasagainofGv=2x15K/(150+1350)=20(26dB).Withacapacitor(orshortcutting)betweenpins1and8,ithasagainofGv=2x15K/150=200(46dB).WhydoestheIC741requiredualpowersupply?Operationalamplifiershavetwopowersupplyrailsbecausetheyusuallyneedtoswingbipolar-outputvoltagesthatgoeitherpositiveornegativeinresponsetothenormalrangeofinputsignals....Withoutthedualsuppliestheoutputsignalwouldclipatthegroundpotential.HowdoIcheckmy741IC?Testinga741ICThecircuitiscommonlycalledasvoltagefollower.Avoltageisappliedtopin3oftheop-ampthroughthevariableresistor(10K).AllweneedtodoistoverifywhetherthevoltagesV1andV2areexactlysameornot.Checkthemusingamulti-meter.WhatisIC741?Anopampisacomplexelectronicdevice,whichconsistsofresistors,capacitors,transistorsanddiodes.Itiscommerciallyavailableinintegratedcircuitform.MostcommonlyavailableandusedopampICisIC741.TheIC741isasmallchip.Itcompriseseightpins.Whatisgainbandwidthproductof741?Gain-BandwidthProduct:ForanOp-Ampthegain,Gisdefinedasthegainwhenasignalisfeddifferentiallyintotheop-ampandnofeedbackloopispresent....ItisgenerallygiveninV/s,andforthe741op-ampissomethingcloseto1v/s.WhatarethefeaturesofIC741?Shortcircuitandoverloadprotectionprovided.Intheory,thedcoutputvoltagewillbezeroifboththeinputsofthe741ICareconnectedtotheground.Lowpowerconsumption.Largecommonmoderejectionratio(CMRR)anddifferentialvoltageranges.Noexternalfrequencycompensationisrequired.Whichop-amp(LM356orLM741)isthebetterchoiceforhigherfrequencyapplications?Um,theLM356isanaudiopoweramplifierwitha300KHzbandwidth.TheLM741isanoperationalamplifierwithatypicalunitygainbandwidthof1MHz.Inotherwords,theyareentirelydifferentsortsofthingsandnotatallinterchangeable.Neitherisverygoodathigherfrequencies.YoumightbethinkingoftheLF356,whichisaJFETinputoperationalamplifierwithaunitygainbandwidtharound5MHz.MuchbetterpartinalmosteverydimensionthantheLM741.CanweuseanLM324insteadofanLM741forconstructinganop-ampintegrator?Yes.Itwilllikelyperformslightlybettertooasithasaslightlybetterspecification(frequency,slewrate,etc),plusyougetfouridenticalopampsinasingle14pinpackage.

IntroductionTheLM2576seriesofmonolithicintegratedcircuitsprovidealltheactivefunctionsforastep-down(buck)switchingregulator.LM2576seriesarecapableofdrivinga3Aloadwithexcellentlineandloadregulation.Theregulatorsaresimpletousebecausetheyrequireaminimumnumberofexternalcomponentsandincludeinternalfrequencycompensationandafixed-frequencyoscillator.CatalogIntroductionCatalogIVoltageStabilizingCircuitIIBuckCircuitIIICurrentBoostCircuitFAQOrdering&QuantityIVoltageStabilizingCircuitThebasicvoltagestabilizingcircuitcomposedofLM2576onlyneedsfourperipheraldevices,anditscircuitisshowninFigure1.TheselectionofinductanceL1dependsontheoutputvoltage,maximuminputvoltageandmaximumloadcurrentofLM2576.First,theeletricvoltagemicrosecondconstant(ET)canbecalculatedaccordingtothefollowingformula:ET=(Vin-Vout)TImes;Vout/VinTImes;1000/f(1)VinisthemaximuminputvoltageofLM2576;VoutistheoutputvoltageofLM2576;fistheoperatingoscillationfrequencyvalueofLM2576(52khz).Figure1.VoltageStabilizingCircuitGenerally,theinputcapacitanceCininthecircuitshouldbegreaterthanorequalto100F.wheninstalling,itisrequiredtobeclosetotheinputpinoflm2576asfaraspossible,anditswithstandvoltagevalueshouldmatchthemaximuminputvoltagevalue.ThevalueoftheoutputcapacitorCout(unitF)shouldbecalculatedaccordingtothefollowingformula:C13300Vin/VoutTImes;L(2)VinisthemaximuminputvoltageofLM2576;VoutistheoutputvoltageofLM2576;L(unitH)isthevalueofinductanceL1.ThewithstandvoltagevalueofcapacitorCshouldbe1.5~2timesofratedoutputvoltage.For5Vvoltageoutput,itisrecommendedtousecapacitorwithvoltagewithstandvalueof16V.TheratedcurrentofdiodeD1shouldbe1.2timesofthemaximumloadcurrent.Consideringthestateofshortcircuitandload,theratedcurrentofthediodeshouldbegreaterthanthemaximumcurrentlimitofLM2576.Thereversevoltageofthediodeshouldbegreaterthan1.25timesofthemaximuminputvoltage.TheselectionofVinshouldconsidertheinputvoltagevalueofLM2576correspondingtothelowestACvoltagedrop(Vac-min)andtheminimuminputallowablevoltagevalueVminofLM2576.Therefore,Vincanbecalculatedaccordingtothefollowingformula:Vin(220Vmin/Vac-min)IftheminimumallowableACvoltagedropis30%(Vac-min=154V)andthevoltageoutputoftheLM2576is5V(Vmin=8V),whenVac=220V,theinputDCvoltageoftheLM2576shouldbegreaterthan11.5V,usually12V.IIBuckCircuitThebuckcircuitcomposedofLM2576isshowninFigure2.TheoutputvoltageisdividedandsampledbyR1andR2,andthensenttothepositiveinputendofthesubtractor.ThenegativeterminalisconnectedtoVSET.TheVSETsignalisthevoltagesignalgivenbythemicrocontroller.TheerrorsignalisobtainedbytheoutputsamplevoltagesubtractingtheD/Aconversionvoltage.Thenaddtheerrorsignaltothereferencevoltage(VREF)1.23V,andsendthisresulttothefeedbackterminalofLM2576.Figure2.BuckCircuitComparedwithtraditionaldirectfeedback,thefeedbackloopinthisdesignismorecomplicated.Thisdesignismainlyduetothefollowingconsiderations:First,itiseasytocontrolsinglechipmicrocomputer.AslongastheoutputvoltageofD/Aconversionischanged,thefeedbackloopworks,andtheoutputsamplingvoltageisautomaticallyapproachedtotheD/Aconversionvoltage.Thenthevoltageadjustmentprocesscomplete.Second,itcanmeetthedesignrequirementsofzerovoltageoutput.IfsimplyusethefeedbackpinoftheLM2576,theminimumoutputofthereferencecircuitgiveninthemanualcanonlyreach1.25V,soyouneedtoshiftthefeedbackvoltagetoaVREFreferencevoltagelevel.ThevoltagedividedbythefeedbackresistorisalsosenttotheDACofthemicrocontroller.IIICurrentBoostCircuit(a)Fixedoutputtype;(b)adjustableoutputtypeFigure3.CurrentBoostCircuitFAQWhereisLM2576used?LM2576isusuallyusedasavoltagestabilizingdevicewhentheinputandoutputvoltagedifferenceislargeandtheoutputcurrentisalsolarge.Becauseitisaswitchingregulator,ithasahigherconversionefficiencyandlowheatgenerationthanalinearregulator.WhatsthedifferencebetweenLM2576T-ADJandLM2576S-ADJ?LM2576T-ADJisthepackageofTO-220,LM2576S-ADJisthepackageofTO-263-5,thereisnodifferenceintheirfunctions.WhatisthedifferencebetweenLM2940andLM2576?Whichcircuitaretheyapplicableto?LM2940isalow-dropoutlinearstabilizedintegratedcircuit.Thelinearstabilizedpowersupplyischaracterizedbyarelativelysimplecircuit,highprecision,andsmallripplecoefficient.Itissuitableforprecisionpowersupplieswithhighvoltagerequirements.ThedisadvantageisthattheefficiencyisverylowandtheoutputThecurrentisrelativelysmall(relativetotheswitchingpowersupply)LM2576isaswitchingpowersupplyintegratedcircuit.Switchingpowersupply,thecircuitismorecomplicated,buttheoutputcurrentislarge,theefficiencyishigh,thedisadvantageisthattheaccuracyislowerandtheripplecoefficientislarger.WhydoswitchingpowersupplychipsLM2576andLM2596havediodes,inductorsandcapacitorsbehindtheoutputpins?ThefunctionofthediodeandtheinductanceisthattheoutputcurrentcanbecontinuouswhentheLM25XXisintheoffstate,andthefunctionofthecapacitoristopreventtheoutputvoltagefromsuddenchangeswhentheLM25XXisturnedonandoff.Infact,itisfiltering.WhythehighertheswitchingfrequencyofLM2576andLM2596,thesmallertheoutputinductanceandcapacitancevalue?Quitesimply,thecapacitivereactanceofacapacitordecreasesasthefrequencyincreases,andtheinductanceofaninductorincreasesasthefrequencyincreases.Thatistosay,theeffectofusinganinductanceof33uHinthecaseof150Khzisbasicallythesameastheeffectofusinganinductanceof100uHinthecaseof52khz,andtheprincipleofcapacitanceisthesame.LM2596isanupgradedversionofLM2576.ButLM2576alsohastheadvantageoflessswitchinglossandlessinterference.IntrodcutionTheCD4066isaquadbilateralswitchwhichcanbeappliedforswitchingofanalogsignalsanddigitalsignals.Itispin-for-pincompatiblewiththeCD4016Bdevice,butexhibitsamuchloweron-stateresistance.Inaddition,theon-stateresistanceisrelativelyconstantoverthefullsignal-inputrange.TheCD4066deviceconsistsoffourbilateralswitches,eachwithindependentcontrols.Theswitchescanbeswitchedoffindependentlyandcomplementeachother.Thisconfigurationeliminatesthevariationoftheswitch-transistorthresholdvoltagewithinputsignaland,thus,keepstheon-stateresistancelowoverthefulloperating-signalrange.Theadvantagesoversingle-channelswitchesincludepeakinput-signalvoltageswingsequaltothefullsupplyvoltageandmoreconstanton-stateimpedanceovertheinput-signalrange.CatalogIntrodcutionITestCircuitofCD4066IICordlessTelephoneIIISelf-lockingTouchSwitchCircuitIVElectronicSwitchCircuitFAQOrdering&QuantityITestCircuitofCD4066ThetestofCD4066quadbilateralswitchismainlytotestthecontrolfunctionandbilateralconductionfunctionofeachswitch.Figure1.TestCircuitofCD4066InFigure1,selectinghighorlowlevel,KIisaSPDTswitchatthecontrolterminal,whichisusedtochangetheonstateoftheanalogswitch.WhentheswitchisturnedtoHtoturnonthehighlevel,thecontrolterminalsofthefourswitchesareathighlevel,andeachswitchshouldbeturnedon.WhentheswitchisturnedtoLlowlevel,thefourswitchesshouldbeturnedoff.K2isadouble-poledouble-throwswitch.ToggletheswitchK2tocontrolthedirectionofthebilateralflowingswitchsignal.ItisindicatedbytwogroupsofredandgreenLED.WhentheswitchK2-1isturnedtoHhighlevel,K2-2isconnectedtoLlowlevel.WhenKIswitchisturnedtohighlevelstate,allswitchesareinforward(reverse)conductionstate.Sothepositivepoleofthepowersupplyisaddedtotheparallelconnectedlight-emittingdiodesLFD1,LED3,IED5,positivepoleofLED7andthestep-downresistorR.ThenthefourredLEDslightup.WhentheKlswitchisturnedtoLlowlevel,eachanalogswitchisinthecut-offstate.NomatterK2isswitchedtoHorLstate,thetwogroupsofredandgreenLEDwillnotlightup.IICordlessTelephoneCD4066isaquadbilateralswitch,whichiswidelyusedinTV,DVDplayer,telephone,variouselectronicinstrumentsandmeters.TheCD4066deviceconsistsoffourbilateralswitches,eachwithindependentcontrols.Theswitchescanbeswitchedoffindependentlyandcomplementeachother.ThetypicalapplicationcircuitofCD4066incordlesstelephoneisshowninthefigure.Figure2.CircuitofCordlessTelephoneIIISelf-lockingTouchSwitchCircuitIntheself-lockingtouchswitchcircuitcomposedofCD4066b,whenthetouchswitchS1isactivated,R4isdriventohighlevel,andthecontrolvoltagebecomeshigh,whichwilllatchtheswitch.WhenS2isactivated,R4becomeslowandthecontrolvoltagebecomeslow,whichwilldeactivatetheswitch.Figure3.Self-lockingTouchSwitchCircuitIVElectronicSwitchCircuitElectronicswitchcircuitcomposedofCD4017andCD4066isshownbelow.Figure4.ElectronicSwitchCircuitFAQWhatisCD4066?TheCD4066isaQuadBilateralSwitchIC,thatis,ithasfourswitcheswhichcanbecontrolledindividualusingacontrolpin.Theseswitchescanconductinboththedirectionsmakingitbilateral,itiscommonlyusedformultiplexinganalogordigitalsignals.HowtouseCD4066?TheCD4066ICconsistsoffourswitches.Itcanswitchanalogsignalsthroughdigitalcontrol.Ananalogsignalisappliedattheinputoftheswitch.IfaHIGHor1valueisfedintothecontrolinput,theanalogsignalwillbepassedfrominputtotheoutputofaswitch.HowCD4066work?The4066reallyfunctionsasananalogswitch.The4066isanICcomposedofswitcheswhicharedesignedtoswitchanalogsignalsviadigitalcontrol....The4066isaquadbilateralswitchcircuit,meaningthatiscomposedof4switches.Eachswitchhasasingleinputandasingleoutputterminal.WhataretheapplicationsofCD4066?TheCD4066isabi-directionalanalogswitchingICsimilartoCD4016,itiscommonlyusedinmultiplexingapplications;itcanalsobeusedtoisolatesignals.Theswitchisbilateralandhencecanbeusedforbothdigitalandanalogsignals.WhatsthedifferencebetweenCD4016andCD4066?ThemajordifferencebetweenbothisthatCD4066hasverylowinternalresistance,accordingtothedatasheetitcanonly5ofon-stateresistanceascomparedwith200ofCD4016IC.

IntroductionTheCD4066isaquadbilateralswitchwhichcanbeappliedforswitchingofanalogsignalsanddigitalsignals.Itconsistsoffourindependentanalogswitches,eachwiththreeterminals:input,outputandcontrol.Whenthecontrolterminalisappliedwithhighpowerlevel,theswitchison.Whenthecontrolterminalisaddedwithlowpowerlevel,theswitchisclosed.Theinputterminalandoutputterminalcanbeusedinterchangeably.Thisconfigurationeliminatesthevariationoftheswitch-transistorthresholdvoltagewithinputsignaland,thus,keepstheon-stateresistancelowoverthefulloperating-signalrange.Theadvantagesoversingle-channelswitchesincludepeakinput-signalvoltageswingsequaltothefullsupplyvoltageandmoreconstanton-stateimpedanceovertheinput-signalrange.ThisarticleintroducestwoapplicationexamplesofCD4066analogswitch.CatalogIntroductionCatalogITrack-and-HoldCircuitofSignalIIInterchangingDisplayCircuitofFourWaysofElectronicSignalFAQOrdering&QuantityITrack-and-HoldCircuitofSignalFigure1.Track-and-HoldCircuitofSignalTheanalogsignalUiisfromthein-phaseinputoftheoperationalamplifier.Whenthecontrolterminaloftheanalogswitchisathighlevel,theanalogswitchison,andthecapacitorCischargedtoUi.Thisprocessiscalledthesamplingoftheinputsignal.Whenthesamplingisover,thecontrolterminaloftheanalogswitchislowlevelandtheanalogswitchisoff.Becausetheresistanceisashighas100Mwhentheanalogswitchisoff,andtheinputimpedanceofoperationalamplifierA2isalsoveryhigh,thesamplingsignalcanbemaintainedonthecapacitorC.IIInterchangingDisplayCircuitofFourWaysofElectronicSignalAgeneralsinglelineoscilloscopecanonlydisplayonecontinuoussignal.Butthisdevicecandisplayfourcontinuoussignalssimultaneouslyinasinglelineoscilloscope.Itisveryconvenienttocomparethetimerelationofdifferentsignals.Figure2.InterchangingDisplayCircuitofFourWaysofElectronicSignalFigure2isthecircuitdiagramofthedevice.ItusesaCD4017counterandoscillatortoformafour-beatcircuittocontrolthefouranalogswitchesintwoCD4066.AdjustableDClevelandoneinputsignalareaddedrespectivelyoneachpairofanalogswitches.Whenthecontrolendoftheanalogswitchishighlevel1,theanalogswitchison.TheDClevelandinputsignalaresenttothey-axisinputendoftheoscilloscope.BecausethefoursignalscorrespondtodifferentDClevels,thefoursignalsdisplayseparatelyontheoscilloscope.AlthoughthefourpairsofanalogswitchesarecontrolledbythecountersQ0,Q1,Q2,Q3outputterminal,theflickerofthewaveformissmallduetothehighoscillationfrequencyoftheoscillator.FAQWhatisCD4066?TheCD4066isaQuadBilateralSwitchIC,thatis,ithasfourswitcheswhichcanbecontrolledindividualusingacontrolpin.Theseswitchescanconductinboththedirectionsmakingitbilateral,itiscommonlyusedformultiplexinganalogordigitalsignals.HowtouseCD4066?TheCD4066ICconsistsoffourswitches.Itcanswitchanalogsignalsthroughdigitalcontrol.Ananalogsignalisappliedattheinputoftheswitch.IfaHIGHor1valueisfedintothecontrolinput,theanalogsignalwillbepassedfrominputtotheoutputofaswitch.HowCD4066work?The4066reallyfunctionsasananalogswitch.The4066isanICcomposedofswitcheswhicharedesignedtoswitchanalogsignalsviadigitalcontrol....The4066isaquadbilateralswitchcircuit,meaningthatiscomposedof4switches.Eachswitchhasasingleinputandasingleoutputterminal.WhataretheapplicationsofCD4066?TheCD4066isabi-directionalanalogswitchingICsimilartoCD4016,itiscommonlyusedinmultiplexingapplications;itcanalsobeusedtoisolatesignals.Theswitchisbilateralandhencecanbeusedforbothdigitalandanalogsignals.WhatsthedifferencebetweenCD4016andCD4066?ThemajordifferencebetweenbothisthatCD4066hasverylowinternalresistance,accordingtothedatasheetitcanonly5ofon-stateresistanceascomparedwith200ofCD4016IC.IDescriptionIndailylife,calendarclocksareusedinvariousplaces.Suchasshoppingmalls,supermarkets,offices,homes,schools,etc.Comparedwiththetraditionalmechanicalclock,thedigitalcalendarclockhasaseriesofadvantages.Suchashighprecision,intuitivedisplay,andlonglife.ThisblogintroducesacalendarclockdesignedwithaDS1302rtcchip.DS1302RTCwithArduinoTutorialCatalogIDescriptionIISystemHardwareDesign2.1OverallStructure2.2DS1302ClockModule2.3LCD1602LCDModuleIIISystemSoftwareDesign3.1DesignofDS1302ClockSubprogram3.2LCD1602LiquidCrystalDisplaySubprogramDesignIVConclusionFAQOrdering&QuantityIISystemHardwareDesign2.1OverallStructureTakeAT89C51single-chipmicrocomputerasthemaincontroller,anduseDS1302clockchiptodesigncalendarclock.ItsoverallstructureisshowninFigure1.Figure1.OverallStructureofSystemThedesignedcalendarclockmustnotonlydisplayhours,minutesandseconds,butalsodisplayyears,months,daysandweeks.ThecoreofthesystemistheAT89C51microcontroller.Throughthesingle-chipcomputercontrolDS1302displaycalendarandtime.AndtheoutputresultisdisplayedonLCD1602liquidcrystalscreen.2.2DS1302ClockModuleTheDS1302clockchiphasthecharacteristicsoflowpowerconsumptionandhighperformance.Itcancommunicatewiththemicrocontrollerthroughasimplesynchronousserialmode,andonlyrequiresthreeI/Olines.Namelyreset(RST),I/Odatalineandserialclock(SCLK)2.2.1DS1302PinsandStructureFigure2showstheexternalpinsandfunctionsofDS1302.Figure2.DS1302PinoutVCC2-mainpowersupplypin;X1,X2-32.768kHzcrystaloscillatorpin;GND-ground;VCC1-batterypin;SCLK-serialclock;I/O-datainput/output;RST-reset.TheinternalstructureofDS1302isshowninFigure3,whichismainlycomposedofthefollowingparts:real-timeclock,datamemoryRAM,oscillatorcircuitandfrequencydivider,inputshiftregister,commandandcontrollogicandsoon.2.2.2DS1302RegistersandcontrolcommandsTheDS1302clockchiphas7registersrelatedtothecalendarclock,asshowninTable1.ThecommunicationsignalbetweenDS1302andsingle-chipmicrocomputerisrealizedthroughsimplesynchronousserialcommunication.AccordingtotheworkingtimingrequirementsofDS1302,whetherthesingle-chipmicrocomputerperformsreadoperationcommunicationfromDS1302orthesingle-chipcomputerperformswriteoperationcommunicationtoDS1302,eachcommunicationisinitiatedbythesingle-chipcomputerfirst.Inotherwords,beforeexecutingthecorrespondingreadorwriteoperation,themicrocontrollermustwriteabyteofcommandwordtoDS1302.Theeight-bitdataofthebytecommandwordisshowninFigure4.Figure4.CommandwordstructureofDS13022.3LCD1602LCDModuleTheLCD1602screencandisplaytwolinesofcharacters,16charactersperline,foratotalof32characters.Thereisan80*8-bitdisplaydatamemoryDDRAMbufferinLCD1602.SeeTable2forthecorrespondencebetweencharacterdisplaybitsandDDRAMaddress.TheaddressonthefirstlineofDDRAMstartsat00Handendsat27H.Theaddressesonthesecondlinestartat40Handendat67H,with40addressesperline.AndLCD1602displays16charactersperline.Therefore,whenwritingaprogram,selectthefirst16addressesofDDRAM.Itisimportanttonotethatthesecondlineaddressstartsfrom40H.IfyouwanttodisplayacharacterinacertainrowandcertaincolumnoftheLCD1602screen,writetheASCIIcodecorrespondingtothischaracterintothecorrespondingDDRAMaddressofacertainrowandcertaincolumn.Atthistime,youwillfindthatthecharactercannotbedisplayednormallyontheLCDscreen.Thereasonisthat80Hmustbeaddedtotheaddress.Forexample,todisplaythesymbolVinthesecondrowandsecondcolumnofthevoltageunitvolts,firstadd80HtothecorrespondingDDRAMaddress41Hinthesecondrowandsecondcolumn,thatis,C1H.ThenwritetheASCIIcode0x56correspondingtotheVcharacterintheC1Haddress.Onlythencanitbedisplayednormally.Thedisplayofothercharacterscanbededucedbyanalogyandwillnotberepeatedhere.IIISystemSoftwareDesignThesoftwareprogrammainlycompletesthefunctionsofdatareading,conversionandliquidcrystaldisplayofthecalendarclock.3.1DesignofDS1302ClockSubprogramsbitRST=P1^0;//DS1302resetportisdefinedinP1.0pinsbitSCLK=P1^1;//TheDS1302clockoutputportisdefinedontheP1.1pinsbitDATA=P1^2;//TheDS1302dataoutputportisdefinedontheP1.2pin(1)Theprogramthatthesingle-chipmicrocomputerwritesabyteofdatatoDS1302voidwright1302(unsignedchardate){Unsigneedchari;SCLK=0;//BepreparedfortherisingedgetowritedataDelaynus(2);for(i=0;i8;i++)//Writeeight-bitdatacontinuously{DATA=date0x01;//Writethebit0dataofdateintoDS1302Delaynus(2);SCLK=1;//WritedataonrisingedgeDelaynus(2);SCLK=0;//date=1;//moveoneplacetotheright}}(2)Theprogramforthesingle-chipmicrocomputertoreadabyteofdatafromDS1302unsignedcharreadd1302(void){Unsignedchari,date;Delaynus(2);for(i=0;i8;i++)//Continuouslyreadeight-bitdata{Date=1;//shiftonebittotherightif(DATA==1)//Ifthedatareadoutis1date|=0x80;//Takeout1andwriteitinthehighestbitofdateSCLK=1;//SetSCLKtoahighlevel,readoutforthefallingedgeDelaynus(2);SCLK=0;//PulldownSCLKtoformthefallingedgeofthepulseDelaynus(2);}returndate;//Returnthereaddata}3.2LCD1602LiquidCrystalDisplaySubprogramDesignThedriverprogramofLCD1602LCDscreenisrelativelycomplicatedtocompile,sowemustfigureouttheusageandmeaningofeachoperationinstructionof1602.Mainlyincludethefollowing:DisplaymodesettingDisplayswitchcontrolInputmodecontrolReaddatafromDDRAMWritedatatoDDRAMClearscreen,cursorhomesettingDataaddresspointersettingLCDscurrentbusyworksign...Partofthecodedesignisasfollows:voidLcd_initial()//InitializeLCD{E=0;Lcd_writecmd(0x38);//16*2display,5*7dotmatrixMsdelay(1);Lcd_writecmd(0x08);//displayoffMsdelay(2);Lcd_writecmd(0x01);//displayclearscreenMsdelay(2);Lcd_writecmd(0x06);//Setthecursor,afterreadingandwritingacharacter,thecursorincreasesby1Msdelay(1);Lcd_writecmd(0x0c);//displayison,nocursorisdisplayedMsdelay(1);}Figure5.HardwarepowersupplydiagramofDS1302calendarclockIntheMedwinV3.0developmentenvironment,useC51languagetocompilethesystemprogram,compileanddebug.AndloadtheHEXhexadecimalfilegeneratedbycompilingintotheMCUchip.StartthesimulationandyoucanseethesimulationrunningeffectoftheDS1302calendarclockdesignsystembasedon1602LCDdisplay.Forexample,thecurrenttimeis11:42:25onMay28,2019,andthesimulationresultisshowninFigure6.Figure6.SimulationresultsofcalendarclockItcanbeseenfromFigure6thatthecurrentdateandtimecanbedisplayedontheLCDscreeninrealtimeandaccurately.IVConclusionCalendarclocksareeverywhereinourlives.ThistexttakesAT89C51single-chipmicrocomputerasthemaincontroller,andusesDS1302real-timeclockchiptodesignthecalendarclocksystem.Inaddition,thehardwarecircuitwasdesignedintheProteussimulationsoftware,andthecorrespondingC51programwaswrittenintheMedwinV3.0developmentenvironment.Thejointuseofthesetwosoftwares,ProteusandMedWinV3.0,greatlyimprovestheefficiencyofsingle-chipsystemdesign,reducescosts,andshortensthedevelopmentcycle.FAQWhatisDS1302?DS1302isatickle-chargetimekeepingchipwhichcontainsareal-timeclock/calendarand31bytesofstaticRAM.DS1302usesserialcommunicationtointeractwithmicrocontrollers.Also,itautomaticallyadjustthedateforthemonthwithfewerdays.WhatdoesanRTCdo?Areal-timeclock(RTC)isacomputerclock(mostoftenintheformofanintegratedcircuit)thatkeepstrackofthecurrenttime.Althoughthetermoftenreferstothedevicesinpersonalcomputers,serversandembeddedsystems,RTCsarepresentinalmostanyelectronicdevicewhichneedstokeepaccuratetime.HowdoyouuseRTC?WiringItUp.5VisusedtopowertotheRTCchipwhenyouwanttoqueryitforthetime.Ifthereisno5Vsignal,thechipgoestosleepusingthecoincellforbackup.ConnectGNDtocommonpower/dataground.ConnecttheSCLpintotheI2CclockSCLpinonyourArduino....ConnecttheSDApintotheI2CdataSDApinonyourArduino.