Tkool Electronics

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.

VSLY5940-VISHAY

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.

DescriptionTIP122isanNPNDarlingtontransistor.Darlingtontransistormeanstherearetwotransistorinonepackageconnectedtoincreasegainatoutput.TIP122transistorhasalotofgoodfeatureslike5Acollectorcurrent,maxemitter-basevoltageis5V,maxcollectordissipationis65watt,minimummaximumcurrentgainisequalto1000.Thistransistorisdesignedtouseasaswitchandforamplificationpurposes.CatalogDescriptionTIP122ComponentDatasheetTIP122PinoutTIP122FeaturesTIP122ApplicationsTIP122EnvironmentalandExportClassificationsTIP122ParametersWorkingofTIP122HowtoSafelyLongRuninaCircuitDarlingtonCircuitSchematicWheretouseTIP122HowtouseTIP122TIP122ReplacementandEquivalentComplementofTIP122TIP122AlternativeNPNTransistorsTIP122SameFamilyTransistorsAdditionalResourcesFAQOrdering&QuantityTIP122ComponentDatasheetResourceTypeLinkDatasheetsTIP120-22TIP120-22,TIP125-27TO220B03PkgDrawingPCNObsolescence/EOLMultipleDevices19/Jun/2009MultDeviceEOL19/May/2017PCNDesign/SpecificationHeatsinkDesingChanges24/Feb/2014Logo17/Aug/2017PCNPackagingTapeandBox/ReelBarcodeUpdate07/Aug/2014MultDevices24/Oct/2017HTMLDatasheetTO220B03PkgDrawingTIP122PinoutPinNumberPinNameDescription1BaseItgovernsthebiasingofthetransistorandworkstoturnONorOFFthetransistor.2CollectorCurrentflowsinthroughcollector,usuallyconnectedtoload3EmitterCurrentcomesoutbytheemitter,itisusuallylinkedtoground.TIP122FeaturesHighDCCurrentGainhFE=2500(Typ)@IC=4.0AdcCollectorEmitterSustainingVoltage@100mAdcVCEO(sus)=60Vdc(Min)TIP120,TIP125=80Vdc(Min)TIP121,TIP126=100Vdc(Min)TIP122,TIP127LowCollectorEmitterSaturationVoltageVCE(sat)=2.0Vdc(Max)@IC=3.0Adc=4.0Vdc(Max)@IC=5.0AdcMonolithicConstructionwithBuiltInBaseEmitterShuntResistorsPbFreePackagesareAvailable*TIP122ApplicationsAudioAmplifierAudioAmplifierStagesAudioPreamplifiersSwitchingLoadsUnder5ATIP122EnvironmentalandExportClassificationsAttributeDescriptionRoHSStatusRoHSnon-compliantMoistureSensitivityLevel(MSL)1(Unlimited)TIP122ParametersBaseProductNumberTIP122CategoryDiscreteSemiconductorProducts-Transistors-Bipolar(BJT)-SingleCollector-BaseVoltageVCBO100VConfigurationSingleCurrent-Collector(Ic)(Max)5ACurrent-CollectorCutoff(Max)500ADCCurrentGain(hFE)(Min)@Ic,Vce1000@3A,3VDescriptionTRANSNPNDARL100V5ATO220ABDetailedDescriptionBipolar(BJT)TransistorEmitter-BaseVoltageVEBO5VFactoryPackQuantity200Height9.4mmLength10.67mmManufacturerONSemiconductorManufacturerProductNumberTIP122MaximumCollectorCut-offCurrent200uAMaximumDCCollectorCurrent5AMaximumOperatingTemperature+150CMinimumOperatingTemperature-65CMountingStyleThroughHoleMountingTypeThroughHoleOperatingTemperature-65C~150C(TJ)PackagingBulkPartStatusObsoletePower-Max2WProductTypeDarlingtonTransistorsSeriesTIP122SubcategoryTransistorsTransistorTypeNPN-DarlingtonUnitWeight0.042329ozVceSaturation(Max)@Ib,Ic4V@20mA,5AVoltage-CollectorEmitterBreakdown(Max)100VWidth4.83mmWorkingofTIP122Thistransistorisrecognizedforitshighercurrentgainwhichis1000andhighercollectorcurrent5amperes,therefore,itisusuallyusedtoswitchThistransistorhaslessbaseandemitterVoltageofthemerely5VhenceforthcanbeeffortlesslyorganizedbyaLogicinstrumentsuchasamicrocontrollerThoughprecautionhastobeengagedtocheck,ifthelogicinstrumentscanfontupto120mA.ThoughTIP122hasextraordinarycurrentatcollectorandcurrentgain,itisimpartiallymodesttoswitchtheexpedientmeanwhileithasanEmitter-Basevoltage(VBE)oftheonly5VandIbofmerely120mA.HowtoSafelyLongRuninaCircuitTogetbetterperformancewiththisdarlingtiontransistorwesuggesttoalwaysstayingbelowitsmaximumratings.Donotoperateitincircuitsusingmorethan100V.Donotprovideloadmorethan5A.Alwaysuseasuitablebaseresistortoproviderequiredcurrentatitsbase.Useasuitableheatsinktosaveitfromoverheatinganddostoreoruseitintemperaturebelow-65centigradeandabove+150centigrade.DarlingtonCircuitSchematicWheretouseTIP122Thistransistorisknownforitshighcurrentgain(hfe=1000)andhighcollectorcurrent(IC=5A)henceitisnormallyusedtocontrolloadswithhighcurrentorinapplicationswherehighamplificationisrequired.ThistransistorhasalowBase-EmitterVoltageoftheonly5VhencecanbeeasilycontrolledbyaLogicdevicelikemicrocontrollers.Althoughcarehastobetakentocheckifthelogicdevicecansourceupto120mA.So,ifyoulookingforatransistorthatcouldbeeasilycontrolledbyaLogicdevicetoswitchhighpowerloadsortoamplifyhighcurrentthenthisTransistormightbeanidealchoiceforyourapplication.HowtouseTIP122AlthoughTIPhashighcollectorcurrentandcurrentgain,itisfairlysimpletocontrolthedevicesinceithasanEmitter-Basevoltage(VBE)ofonly5Vandbasecurrentofonly120mA.InthebelowcircuitIhaveusedtheTIP122tocontrola48Vmotorwhichhasacontinuouscurrentofabout3A.Thecontinuescollectorcurrentofthistransistoris5Aandourloadconsumesonly3Awhichisfine.Themaximumbasecurrentisabout120mA,butIhaveusedhighvalueof100ohmresistortolimititto42mA.Youcanuseevena1Kresistorifyourcollectorcurrentrequirementisless.Thepeak(pulse)currentofthistransistoris8Asomakesureyourmotordoesnotconsumemorethanthat.Thisisjustamodelcircuitdiagramthatshowstheworkingonthistransistoritcannotbeusedassuch.So,similarlyyoucancontrolyourloadinthesameway.TIP122ReplacementandEquivalentTIP132,TIP102,NTE261,NTE263,2N6045,2N6045G,2SD2495,BDT65B,2N6532,BDT63B,BDW43,TIP142T(PinconfigurationofsometransistorsmaydifferfromTIP122,checkpinconfigurationbeforereplacinginacircuit)TIP22isadarlingtionpairtransistormanufacturedinTO-220package,itsagoodtransistortouseasahighgainswitchoramplifier.ComplementofTIP122ThecomplementoftheTIP122transistorisTIP127.TIP122AlternativeNPNTransistorsBC547,BC548,BC549,BC636,BC639,2N2369,2N3055,2N3904,2N3906,2SC5200TIP122SameFamilyTransistorsNPNFamilytransistorsareTIP120,TIP121,TIP122,andPNPFamilyareTIP125,TIP126,TIP127(PNP)AdditionalResourcesAttributeDescriptionOtherNamesTIP122FSTIP122FS-NDTIP122FS-NDRTIP122OSFAQWhatisTIP122transistor?TIP122TransistorisanNPNDarlingtontransistor....TIP122Darlingtontransistorhasalotofgoodfeatures,like5Acollectorcurrent,maximumemitter-basevoltageis5V,maximumcollectordissipationis65watt,andsoon.Thistransistorismanufacturedtouseasaswitchandforamplificationpurposes.WhattypeofpackageisusedforTIP122transistor?TheTIP122isasiliconNPNDarlingtontransistorinaTO-220typepackagedesignedforgeneralpurposeamplifierandlow-speedswitchingapplications.HowdoyoutestatransistorTIP122?Harvino.Theproperwaytotestistosetyourdmmtodiodetest(usually2ksettingontheohmscale).Transistorshavethreelegs;anemitter,abase,andacollector.HowdoIknowifmytransistorisblown?Connectthebaseterminalofthetransistortotheterminalmarkedpositive(usuallycolouredred)onthemultimeter.Connecttheterminalmarkednegativeorcommon(usuallycolouredblack)tothecollectorandmeasuretheresistance.Itshouldreadopencircuit(thereshouldbeadeflectionforaPNPtransistor).Whatarethe3terminalsofatransistor?Abipolartransistorhasterminalslabeledbase,collector,andemitter.Asmallcurrentatthebaseterminal(thatis,flowingbetweenthebaseandtheemitter)cancontrolorswitchamuchlargercurrentbetweenthecollectorandemitterterminals.HowtomakeminiaudioamplifieruseTIP122/TIP127transistor?IntroductionLM339(Quaddifferentialcomparator)consistoffourindependentvoltagecomparators.Itisacommonintegratedcircuitandismainlyusedinhigh-voltagedigitallogicgatecircuits.UsingLM339caneasilyformvariousvoltagecomparatorcircuitsandoscillatorcircuits.CatalogIntroductionCatalogICircuitofSingleLimitComparatorIIOverheatDetectionandProtectionCircuitIIIHysteresisComparatorIVOver-voltageDetectionCircuitVDoubleLimitComparatorVIUsingLM339toformanOscillatorFAQOrdering&QuantityICircuitofSingleLimitComparatorFigure(a)showsabasicsinglelimitcomparator.AddtheinputsignalUIN(i.e.voltagetobecompared)tothein-phaseinputterminal,andconnectareferencevoltageUrattheanti-phaseinputterminal.WhentheinputvoltageUinUr,theoutputishighlevelUOH.Figure(b)showsitstransmissioncharacteristics.Figure1.CircuitofSingleLimitComparatorIIOverheatDetectionandProtectionCircuitItispoweredbyasinglepowersupply.Afixedreferencevoltageisaddedtotheanti-phaseinputterminalof1/4LM339,anditsvaluedependsonR1andR2.UR=R2/(R1+R2)*UCC.Thevoltageatthein-phaseterminalisequaltothevoltagedropofthethermistorRT.Whenthetemperatureinsidethemachineisbelowthesetvalue,the+terminalvoltageisgreaterthanthe-terminalvoltage,andUoisahighpotential.Whenthetemperaturerisesabovethesetvalue,the-terminalvoltageisgreaterthanthe+terminal,andtheUooutputisatzeropotential,whichcausestheprotectioncircuittooperate.AdjustingthevalueofR1canchangethethresholdvoltage,whichsetsthetemperaturevalue.Figure2.OverheatDetectionandProtectionCircuitIIIHysteresisComparatorThehysteresiscomparatorcanalsoberegardedasasinglelimitcomparatorwithpositivefeedback.Inthesinglelimitcomparatordescribedabove,iftheinputsignalUinhasslightinterferencenearthethreshold,theoutputvoltagewillproducecorrespondingundulation.Thisshortcomingcanbeovercomebyintroducingpositivefeedbackintothecircuit..Figure(a)showsahysteresiscomparator.ThefamiliarSchmidtcircuitisacomparatorwithhysteresis.Figure(b)showsthetransmissioncharacteristicsofthehysteresiscomparator.Figure3.HysteresisComparatorItisnotdifficulttoseethatoncetheoutputstateischanged,theoutputvoltagewillbestableaslongastheinterferencenearthejumpvoltagevaluedoesnotexceedthevalueofU.Accordingly,itcomestoareductioninresolution.Forthehysteresiscomparator,itcantdistinguishtwoinputvoltageswhosedifferenceislessthanU.Thehysteresiscomparatorwithpositivefeedbackcanacceleratetheresponsespeedofthecomparator,whichisoneofitsadvantages.Inaddition,sincethepositivefeedbackaddedbythehysteresiscomparatorisverystrongandmuchstrongerthantheparasiticcouplinginthecircuit,thehystericcomparatorcanalsoavoidtheself-oscillationcausedbytheparasiticcouplingofthecircuit.IVOver-voltageDetectionCircuitFigure4showsthepartofover-voltagedetectioncircuitinaninductioncookercircuit.Whenthegridvoltageisnormal,1/4lm339u42.8v,thecomparatorturnsover.Theoutputis0VandBG1iscutoff.ThevoltageofU5iscompletelydeterminedbythepartialvoltagevalueofR1andR2,whichis2.7V.ItmakesU4largerthanU5,whichmakesthestateafteroverturningextremelystableandavoidstheinstabilitycausedbythesmallfluctuationofgridvoltageneartheover-voltagepoint.Duetocertainhysteresis,afterovervoltageprotection,theinductioncookerstartstoworkagainwhenthegridvoltagedropsto242-5=237vandU4U3.Figure4.Over-voltageDetectionCircuitVDoubleLimitComparatorThecircuitinFigure5consistsoftwoLM339toformawindowcomparator.WhenthecomparedsignalvoltageUinisbetweenthethresholdvoltages(UR1UinUR2),theoutputishighpotential(UO=UOH).WhenUinisnotbetweenthethresholdpotentialrange,(UinUR2orUinUR1)theoutputislowpotential(UO=UOL),andthewindowvoltageU=UR2-UR1.Itcanbeusedtojudgewhethertheinputsignalpotentialisbetweenthespecifiedthresholdpotential.Figure5.DoubleLimitComparatorVIUsingLM339toformanOscillatorFigure6showsthecircuitofanaudiosquarewaveoscillatorcomposedof1/4LM339.ChangingC1canchangethefrequencyoftheoutputsquarewave.Inthiscircuit,whenC1=0.1uF,f=53Hz;whenC1=0.01uF,f=530Hz;whenC1=0.001uF,f=5300Hz.LM339canalsoformahigh-voltagedigitallogicgatecircuit,andcandirectlyinterfacewithTTLandCMOScircuits.Figure6.LM339OscillatorFAQWhatisLM339?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.

VSLY5940-VISHAY

IIntroductionInthisblog,wecomparetheLM339andLM339NproducedbyTI.Thecontentofcomparisonincludescomponentparameters,packaging,applicationareas,andtheircircuitdiagrams,etc.HopethisblogishelpfultothoseinterestedinLM339orLM339N.LM339NCatalogIIntroductionIIComponentDatasheetIIIDifferenceBetweenLM339andLM339NIVParametersVFeaturesVIApplicationsVIIPinoutFAQOrdering&QuantityIIComponentDatasheetComponentDatasheet1LM339NDatasheetComponentDatasheet2LM339DatasheetIIIDifferenceBetweenLM339andLM339N◾LM339Nisaquadvoltagecomparator.Itadoptsdualin-line14-pinpackage.Themaximumoperatingvoltageis18Vandthepowerconsumptionis265mW.Itisusedininductioncookersandotherproducts.◾LM339(Quaddifferentialcomparator)consistoffourindependentvoltagecomparators.Itisacommonintegratedcircuitandismainlyusedinhigh-voltagedigitallogicgatecircuits.LM339commonmoderangeisverylarge,from0vtothepowersupplyvoltage-1.5v;widesupplyvoltagerange:singlepowersupplyis2-36V;dualpowersupplyvoltageis1V~18V.IVParametersParametersLM339NLM339Numberofchannels(#)44OutputtypeOpen-collector,Open-drainOpen-collectorPropagationdelaytime(s)0.70.3Vs(Max)(V)3630Vs(Min)(V)22Vos(offsetvoltage@25C)(Max)(mV)55Iqperchannel(Typ)(mA)0.20.2Inputbiascurrent(+/-)(Max)(nA)25050Rail-to-railOutOutRatingCatalogCatalogOperatingtemperaturerange(C)0to700to70FeaturesStandardcomparatorStandardcomparatorVICR(Max)(V)3428.5VICR(Min)(V)00Approx.price(US$)1ku|0.241ku|0.05VFeaturesLM339NLM339WideSupplyVoltageRangeLM139/139ASeries2to36VDCor1to18VDCLM2901-N:2to36VDCor1to18VDCLM3302-N:2to28VDCor1to14VDCVeryLowSupplyCurrentDrain(0.8mA)IndependentofSupplyVoltageLowInputBiasingCurrent:25nALowInputOffsetCurrent:5nAOffsetVoltage:3mVInputCommon-ModeVoltageRangeIncludesGNDDifferentialInputVoltageRangeEqualtothePowerSupplyVoltageLowOutputSaturationVoltage:250mVat4mAOutputVoltageCompatibleWithTTL,DTL,ECL,MOS,andCMOSLogicSystemsWideSupplyRangesSingleSupply:2Vto36V(Testedto30VforNon-VDevicesand32VforV-SuffixDevices)DualSupplies:1Vto18V(Testedto15VforNon-VDevicesand16VforV-SuffixDevices)LowSupply-CurrentDrainIndependentofSupplyVoltage:0.8mA(Typical)LowInputBiasCurrent:25nA(Typical)LowInputOffsetCurrent:3nA(Typical)(LM139)LowInputOffsetVoltage:2mV(Typical)Common-ModeInputVoltageRangeIncludesGroundDifferentialInputVoltageRangeEqualtoMaximum-RatedSupplyVoltage:36VLowOutputSaturationVoltageOutputCompatibleWithTTL,MOS,andCMOSOnProductsComplianttoMIL-PRF-38535,AllParametersAreTestedUnlessOtherwiseNoted.OnAllOtherProducts,ProductionProcessingDoesNotNecessarilyIncludeTestingofAllParameters.VIApplicationsLM339NLM339High-PrecisionComparatorsReducedVOSDriftOvertemperatureEliminatesNeedforDualSuppliesAllowsSensingNearGNDCompatibleWithAllFormsofLogicPowerDrainSuitableforBatteryOperationIndustrialAutomotiveInfotainmentandClustersBodyControlModulesPowerSupervisionOscillatorsPeakDetectorsLogicVoltageTranslationVIIPinoutLM339andLM339NsharethesamepinoutdiagramFAQWhatisLM339?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.IDescriptionThisblogmainlydiscussesandsolvesthefollowingproblem:HowtouseLM339voltagecomparatortomakeareservoirwaterlevelgauge?Accordingtowaterlevel,thisdesignperformssignalprocessingandcontrolsthepotentialofmultiplevoltagecomparators,sotheoutputwillchangeaccordingly.Therefore,underitsdrive,LEDcannotonlyemitlight,butalsoachievetheeffectofindicatingthewaterlevel.Figure1.LM339CatalogIDescriptionIIIntroductionIIIWokingPrincipleIVDeviceselectionandComponentProduction4.1deviceselection4.2PartProductionVInstallationandDebugging5.1DetectionPart5.2DisplayPartVIConclusionFAQOrdering&QuantityIIIntroductionDuetoinsufficientwatersupplyinsomeresidentialareas,pumpworkersmustfirststorewaterinthereservoirandthensupplywaterinaregularmanner.Inthisway,thepumpworkermustknowthewaterlevelofthereservoiratanytimeinthepumproom.Inthepast,electrodessuchascopperrodsorstainlesssteelwereusedtodetectthewaterlevelofthepool.However,duetoelectriccorrosion,thefunctionoftheelectrodeislostsoonafteruse.Forthisreason,thisblogusesLM339voltagecomparatortomakewaterlevelgauge.Thisnotonlyeliminatesthepainofoftenchangingelectrodes,butalsosimpleandeasy.Howsimpleisit?Onlytwowiresneedtobeconnectedfromthereservoirtothepumproom.Aftermorethantwoyearsofoperation,itsperformancehasbeenstableandreliable,achievingtheexpectedresults.IIIWokingPrincipleThemaincircuitofthewaterlevelgaugeiscomposedof4LM339voltagecomparators.Thiskindofintegratedcircuithasthecharacteristicsofeasypurchase,lowprice,singlepowersupplyoperationandwidedifferentialrange.EachLM339has4independentvoltagecomparators(15inthisdesign).Aslongasthepotentialdifferencebetweenthepositiveandnegativeinputterminalsis10mV,theoutputterminalcanbereliablyswitchedfromonestatetoanother.Whenthepositiveinputterminalis10mVhigherthanthenegativeinputterminal,itsoutputterminalishigh;Whenthenegativeinputis10mVhigherthanthepositiveinput,itsoutputislow.Inaddition,LEDscanbedrivendirectly.ThenhowtomaketheoutputendofLM339havehighandlowlevelchanges?Inspecificuse,anappropriateresistanceisgenerallyaddedbetweentheoutputterminalandthepositivepowersupply.Thisresistoriscalledapull-upresistor.Thatis,whentheoutputterminalofLM339isinahighimpedancestate,thepotentialoftheoutputterminalispulledupbytheresistor.Figure2.BlockDiagramofWaterLevelGaugeTheprincipleblockdiagramofthedeviceisshowninFigure2.Thevoltagesignalmeasurementconsistsofareedswitchandavoltagedividerresistor.Theringmagnetssuspendedinthewaterareindifferentpositions.Duetotheprincipleofelectromagneticinduction,notonlythecorrespondingdryreedswitchnormallyopencontactsareclosed,butalsothecorrespondingvoltagedividerresistorisconnected.Therefore,thecircuitwillpickupdifferentvoltagesignals.Thepotentialofthenegativeinputterminalofthecomparatorisformedbyafixedvoltagedividerresistor.Themeasuredvoltagesignaliscomparedwiththesetpotential.TheresultofthisisthattheLEDdisplaysthewaterlevelwhendriven.Inaddition,analarmisissuedwhenthehighestwaterlevelisreachedtoremindthepumpertostopwaterinjectiontopreventwateroverflow.TheconcretecircuitisshownasinFig.3.Figure3.WaterLevelGaugeCircuitDiagramInFigure3,thepowersupplyis+12V,andthedepthofthepoolisdividedinto15segmentsfordisplay.Inthispicture:A1~A15arevoltagecomparatorscomposedofLM339;GK1~GK15aredryreedswitches,thenormallyopencontactisclosedwhentheringmagnetisclosetoacertaindryreedswitch;ThevoltagedividercircuitcomposedofresistorsR1toR15determinesthepotentialofthepositiveinputterminalofeachcomparator.ThevoltageofthepositiveinputterminalofLM339changesduetothedifferentpositionsofthemagneticsteel.ThevoltagedividercircuitcomposedofresistorsR01~R030determinesthepotentialofthenegativeinputterminalofeachcomparator.Thepotentialofeachnegativeinputterminalisfixedafterdetermination.Whenthemagneticsteelfloatingonthewatersurfaceisclosetoacertaindryreedswitch,duetothepartialpressureofR1,R2,,R15,thepositiveinputterminalsofthecomparatorsA1,A2,,A15havedifferentinputs.Afterthissignaliscomparedwiththepotentialsetatthenegativeinputofthecomparator,therewillbeacorrespondingoutput.FromFigure3,whenGK1pullsin,itisequivalenttoholdingthemagneticsteelfloatattheupperlimitwaterlevel.Thepositiveinputofeachcomparatorisequaltothegroundpotential,whichislowerthantheirnegativeinput.Therefore,theoutputterminalsarealllowlevel,sothatallLEDsarelit.Atthistime,theoutputofA1dropsfromhighleveltolowlevel,andNE555istriggeredthroughcapacitorC.NE555isconnectedasamonostablecircuit.Oncetriggered,its3pinwilloutputahighlevel,whichwilldrivethebuzzertoalarm.ItsdurationisdeterminedbytheRCcomponentsconnectedtothe6and7pins.WhenGK2isclosed,LED2~LED15shouldbeonandLED1shouldbeoff.Atthistime,thepotentialofthepositiveinputterminalofeachcomparatorishigherthanthepotentialofthenegativeinputterminalofA1andlowerthanthepotentialofthenegativeinputterminalofA2~A15,andsoon.IVDeviceselectionandComponentProduction4.1deviceselectiona.SetthenegativeinputpotentialofeachcomparatortoVsh.Thenegativeinputpotentialofeachcomparatorissetartificiallyaccordingtothenumberofsegmentsdividedintopowersupplyandwaterdepth.Becausethepooldepthhasbeendividedinto15segmentsfordisplay,startingfrom2.0V,thedifferencebetweeneachadjacentnegativeinputterminalis0.4V.AsshowninthefirstrowinTable1.b.Selecttheresistancebetweenthenegativeinputterminalofeachcomparatorandthepowersupply,thatis,thevoltagedividerresistanceR01=R03==R029=20k,settoR.c.CalculatethegroundresistanceR02,R04,...,R030,whichisRr.SupposetheresistanceofthenegativeinputterminaltogroundisRr,andthepotentialofeachnegativeinputterminalisVsh,accordingtocircuitdiagram3:(1)Fromthisformula:(2)Forexample,tomakethepotentialofthenegativeinputterminalofthevoltagecomparatorA1Vsh=2V,accordingtoequation(2),wecangetAsshowninthesecondrowandthefirstcolumninTable1.TheselectionoftheotherresistorsR04,R06,,R030canbecalculatedaccordingtotheaboveformula(theresultisatheoreticalvalue,seethedatashowninthesecondrowinTable1fordetails).d.DeterminethenominalresistanceRbfromRr.Infact,thenominalvalueofcommerciallyavailableresistorsisdifferentfromthiscalculatedvalue.Inspecificapplications,anominalresistanceRbwithasimilarresistancevaluecanbeselected.ThespecificvalueisshowninthethirdrowofTable1.e.DeterminethepotentialVofthenegativeinputterminalofeachcomparatorAbyRb.WhenthenominalvalueofresistanceRbisselected,usethefollowingformulatocheckthepotentialVgeneratedbythisresistance.(3)Thespecificpotentialvalueisshowninthe4throwofTable1,comparedwiththesetvalueinthe1strow,aslongasitdoesnotexceed0.1V.f.DeterminetheresistancesR1,R2,,R15ofthepositiveinputterminalsofeachcomparatorandsetthemasRzh.FirstfindR1,setthepositiveinputpotentialofeachcomparatorasVzh,whenGK1pullsin,itcanbeseenfromTable1that2VVzh2.4V,setVzh=2.2V,R=20k,accordingtoformula(3),itcanbelistedThesolutionisthatRzh=R14.5k.Thisresistanceisnotthenominalvalue.Chooseasimilarnominalvalueof4.8k.ThenfindtheotherresistancesR2,R3,,R15,whichcanallbecalculatedbythismethod.Theresultisthetheoreticalvalue,whichhasaslightdeviationinpractice.Aftercorrection,thevalueisshowninthefifthrowofTable1.Aftertheaboveparametersareselectedinthisway,itcanbeensuredthatwhenthewaterlevelinthepoolreachesthelowestlimitandthefloatholdingthemagneticsteelsinkstothelowestposition,themagneticsteelseparatesfromallthereedswitchesandtheLEDsareallextinguished;AndwhenthefirstreedswitchGK1isclosed(equivalenttothewaterlevelinthepoolreachesthehighestlimit,thefloatholdingthemagneticsteelrisestothehighestposition)LEDsareallon.Whenthefloatisatacertainpositioninthemiddle,thecorrespondingLEDandtheLEDsbelowareallon,andtheLEDaboveitisoff,toshowthewaterlevel.Aftertheabovecalculation,thespecificdatashowninTable1isobtained.4.2PartProductionItisnecessarytomeasuretheheightfromthelowestwaterlevelofthereservoirtothelimitwaterlevel,anddividethisheightinto15segments.Thedistanceofeachsegmentislessthan200mm,thisdistancecanensurethatthemagneticsteelcanalwaysattractanadjacentdryreedswitch,soastoavoiddisplaybreakpoints.Thatistopreventthemagneticsteelfromnotattractingtheupperdryreedpipeorthelowerdryreedpipeduringoperation,sothattheLEDdisplayisallextinguished,causingtheillusionofwaterlessness.FortheconnectionsofGK1,R1~GK15,R15,firstsolderthemtoasmallprintedcircuitboardwithawidthlessthanorequalto20mm,andthenusewirestoconnectthematadistanceoflessthanorequalto200mm,andencapsulatethemina25mmhardplastictube..Theupperandlowermouthsofthepipeshouldbetightlysealedtopreventwaterleakage.Thetubeiscoveredwitharing-shapedmagnet.Afterdroppinganon-ferromagneticheavyobjectonthelowerendofthehardplasticpipe,theplasticpipeisverticallysunkintothebottomofthereservoir.Aringfloatisplacedunderthemagneticsteelandissleevedonthetube,andtheupperendofthetubeisfixedontheobservationportabovethereservoir.Duetothefunctionofthefloat,themagneticsteelisalwayssuspendedonthewatersurface,risingandfallingwiththewatersurface.Notethattheplaneofthemagneticsteelshouldalwaysbeparalleltothewatersurface,andtheplasticpipeshouldbeverticaltothewatersurfacetopreventthemagneticsteelfrombeingstuckbyfrictionwiththepipewallwhenthewaterlevelrisesandfalls.VInstallationandDebuggingThewholedeviceconsistsoftwoparts:Itisadetectionpartcomposedofareedswitchandvariousvoltagedividers;ItisthesignalprocessingdisplaypartcomposedofLM339.5.1DetectionPartBeforeencapsulatingtheplastictube,putsomesilicagelinthetubetoabsorbthemoistureinthetubeandpreventthelineinthetubefromgettingdamp.Ifring-shapedmagneticsteelisusedasthedetectionelement,thereedpipeconnectedinseriesintheplastictubeshouldberealizedbytwostaggeredreedpipes.Accordingtotheelectromagneticinductiontheory,theanalysisofthemagneticfieldlinesofthemagneticsteelshowsthatthereareasmallsectionofmagneticfieldlinesparalleltotheplaneofthemagneticsteelattheupperandloweropeningsofthemagneticsteel.Whenthissectionisclosetothereedswitch,thedirectionofitsmagneticfieldlineisperpendiculartothedirectionofthereedofthereedswitch.Atthistime,althoughthereedswitchisveryclosetothemagneticsteel,thecontactisstillreleasedanddisconnected,whichwillmakealltheLEDsgoout.Iftwostaggeredreedpipesareusedinstead,theproblemcanbesolved,andthestaggereddistancecanbedeterminedinexperiments.5.2DisplayPartThewaterlevelofeachsegmentisdisplayedbygreen10LED,andthelimitwaterlevelisdisplayedbyeye-catchingredLED.IftheLEDsarearrangedneatlytogether,thewaterlevelinthepoolcanbeclearlyseenaccordingtotheonoroffoftheLEDs.Equippedwithabuzzer,itwillgivethepumpworkeraclearerreminder.Note:Fromthedetectorinthepooltothecircuitboardofthepumproom,itisbesttouseshieldedwiretopreventinterferencesignalsfromentering.Weshouldalsonotethatthepowersupplymustberegulated.Fugure4.lm339VIConclusionThenegativeinputpotentialofthevoltagecomparatorA1~A15composedofLM339shouldbesetaccordingtoacertainrule,andthepotentialintervalbetweeneachotherdependsonthedepthofthecell.Ifthewaterlevelisdeeper,theintervalcanbesmaller,andthenumberofsectionscanbeselectedmore.Thepotentialdifferencebetweenadjacentcomparatorsisgenerally0.4V.Ifthepotentialdifferenceislarge,theselectionoftheresistanceiseasy;ifthepotentialdifferenceissmall,becausethenominalvalueintervalofthegeneralresistanceislarge,itisnecessarytouseanadjustableresistortoadjustthepotential.Ofcourse,inthecaseofsmallintervals,thesmallestpotentialdifferencebetweeneachothershouldbegreaterthan10mV,otherwisetheinputcharacteristicsofLM339willnotbeabletodistinguishthepotentialbetweeneachother.Inaddition,thevoltageofthepowersupplyandthenominalvalueofeachresistancemustbeconsidered.Thismethodcanalsobeappliedtootherfields.Suchasmonitoringthewaterdepthofrivers,rivers,lakes,andbays,theoillevelofgasstations,andthedepthofwatertanksinwaterplants.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.I.IntroductionThe74HC595isan8-bitserial-inorparallel-outshiftregisterwithastorageregisterand3-stateoutputs.74HC595withthecharacteristicsofhighspeed,lowpowerconsumptionandsimpleoperation,canbeeasilyusedinMCUinterfacetodriveLEDoperation.ThisarticleintroducesthecircuitdesignofLEDdisplaydrivedby74HC595.CatalogI.IntroductionII.BasicDescription2.1LEDDisplay2.274HC595III.CircuitDesign3.1HardwareCircuit3.2DisplayDriverIV.ConclusionFAQOrdering&QuantityII.BasicDescription2.1LEDDisplayA7SegmentLEDDisplay,alsoknownasLEDdisplay,hasbeenwidelyusedinvariousinstrumentsbecauseofitslowprice,lowpowerconsumptionandreliableperformance.TherearemanytypesofLEDdriversonthemarket,andmostofthemhavemultiplefunctions,butthepriceiscorrespondinglyhigher.Ifusedinasimplesystemwithlowcost,itisnotonlyawasteofresources,butalsoincreasesthecostofproducts.Using74HC595chiptodriveLEDhasvariousdisadvantages.Highspeed,lowpowerconsumption,unlimitednumberofLEDs.ItcancontrolboththecommoncathodeLEDdisplayandthecommonanodeLEDdisplay.Thecircuitdesignedwith74HC595isnotonlysimple,butalsolowinpowerconsumptionandstrongindrivingability.Itisalowcostandflexibledesignscheme.2.274HC595The74HC595isan8-bitserial-in/serialorparallel-outshiftregisterwithastorageregisterand3-stateoutputs.Boththeshiftandstorageregisterhaveseparateclocks.Thedevicefeaturesaserialinput(DS)andaserialoutput(Q7S)toenablecascadingandanasynchronousresetMRinput.ALOWonMRwillresettheshiftregister.DataisshiftedontheLOW-to-HIGHtransitionsoftheSHCPinput.ThedataintheshiftregisteristransferredtothestorageregisteronaLOW-to-HIGHtransitionoftheSTCPinput.Ifbothclocksareconnectedtogether,theshiftregisterwillalwaysbeoneclockpulseaheadofthestorageregister.Datainthestorageregisterappearsattheoutputwhenevertheoutputenableinput(OE)isLOW.AHIGHonOEcausestheoutputstoassumeahigh-impedanceOFF-state.OperationoftheOEinputdoesnotaffectthestateoftheregisters.Inputsincludeclampdiodes.ThisenablestheuseofcurrentlimitingresistorstointerfaceinputstovoltagesinexcessofVCC.Figure1.74HC595FunctionalDiagramFigure2.74HC595LogicSymbolIII.CircuitDesign3.1HardwareCircuitFigure3isadisplaypanelcircuitdesignedwithAT89C2051and74HC595interface.Figure3.CircuitofDisplayPanelTheP115,P116,andP117oftheP1portareusedtocontrolthedisplayoftheLED,andtheyareconnectedtotheSLCK,SCLKandSDApinsrespectively.Threedigitaltubesareusedtodisplaythevoltagevalue.Onthecircuitboard,LED3isonthefarleftandLED1isonthefarright.Whensendingdata,firstsendthedisplaycodeofLED3,andfinallysendthedisplaycodeofLED1.ThebrightnessoftheLEDiscontrolledbytheresistanceofPR1toPR3.2.2DisplayDriverUseDISP1,DISP2,andDISP3tostoredisplaydata.AftertheCPUinitializationiscomplete,calltheLRDISPsubroutinetocleartheregisterof74HC595.ThereisnoneedtocalltheclearsubroutinebeforecallingthedisplaysubroutineDISPLAY.Nowwritethetwosubroutinesasfollows.①CLRDISP:MOVR2,#24CLRBIT:CLRSCLKCLRCMOVSDA,presision resistorsCSETBSCLKDJNZR2,smd resistors sizeCLRBITRET②Display:CLRSLCKMOVR3,semiconductor wafer#3MOVR0,photonic integrated circuits#DISP3DISP1:MOVA,types of capacitors@R0MOVR2,how to read resistor#8DISP2:CLRSCLKRLCAMOVSDA,CSETBSCLKDJNZR2,DISP2DECR0DJNZR3,DISP1SETBSLCKRETIV.ConclusionItcanbeseenfromtheaboveexamplesthattherearenocomplicatedtechnicalproblemsinthedesignofhardwareandsoftwarewhen74HC595isusedtodesignLEDdrivercircuit.Inaddition,74HC595canbeusednotonlytodriveLEDdisplays,butalsotodrivelight-emittingdiodes.Each74HC595candrive8LEDssimultaneously.Thissolutionisidealwhenthevolumerequirementsoftheproductarenothighandwanttoreducethecost.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.

VSLY5940-VISHAY

DescriptionLED,asthefirstbasicfunctiontobecompletedinMCUlearning,playsaveryimportantroleinMCUlearners,whichalsocalledmagiclampbyMCUlearners.IbelievethateveryoneseesmostandthesimplestLEDcircuitisthefigureshownbelow.Asshowninthefigure,notonlythecircuitissimple,butalsoitsoperationisverysimple.GiveselectricalleveltoI/OcorrespondingtoeightLEDs,andthecorrespondingLEDcanbeonoroff.Figure1.simpleLEDcircuitCatalogDescription74HC595Drives8BitsLEDSFAQOrdering&Quantity74HC595Drives8BitsLEDSButnotallLEDcircuitsaresosimple.Somecircuitswilluse74HC595chiptodrive8LEDsordrivethe8-bitdigitaltubesegmentcode,asshowninthefigurebelow.Figure2.74HC595drives8LEDsWhyisasimplecircuitsocomplicated?Thereasonisobvious.BeforetheeightLEDneedeightI/O,nowonlythreeI/OcandriveeightLED.Letsbrieflyintroduce74CH595anduseitsuccessfullytodriveeightLEDlights.The74HC595isan8-bitserial-inorparallel-outshiftregisterwithastorageregisterand3-stateoutputs.Boththeshiftandstorageregisterhaveseparateclocks.Thedevicefeaturesaserialinput(DS)andaserialoutput(Q7S)toenablecascadingandanasynchronousresetMRinput.SIisitsserialdatainput.Q0toQ7aredataoutput.SCK,istheclockfortheshiftregister.The595isclock-drivenontherisingedge.Thismeansthatinordertoshiftbitsintotheshiftregister,theclockmustbeHIGH.Andbitsaretransferredinontherisingedgeoftheclock.RCK,isaveryimportantpin.WhendrivenHIGH,thecontentsofShiftRegisterarecopiedintotheStorage/LatchRegister;whichultimatelyshowsupattheoutput.Sothelatchpincanbeseenaslikethefinalstepintheprocesstoseeingourresultsattheoutput.SQHisserialdataoutput.Whatwewanttoachievenowistomovethe8-bitsdataofSIinto74HC595onebyoneundertheactionofSCKandRCKandpresenttheminparallelonQ0-Q7.Figure3.How74HC595ShiftRegisterworksWheneverweapplyaclockpulsetoa595,thebitsintheShiftRegistermoveonesteptotheleft.Belowisitscode.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.Whatisadigitaltube?Lightemittingdiodeconnectstheanodetogetherandthenconnectedtothepowerofpositiveiscalledcommonanodedigitaltube,lightemittingdiodeconnectedtothecathodeandthenconnectedtothepowerofthecathodeiscalledcommoncathodedigitaltube.Whatisthedifferencebetweenshiftregisterandcounter?Inashiftregister,theinputofelementNistheoutputofelementN-1,andallelementsusethesameclock.Inacounter,theinputofelementNistheinverseofitsoutput,andtheclockofelementN+1istheoutputofelementN.IDescriptionDoyouknowwhattheDigitalTubeDisplayneeds?Thedisplayofthedigitaltuberequiresadigitaltubeandacontrolcircuitofmultipledigitaltubes.Takethesingle-chipmicrocomputercontrolcircuitofan8-bitdigitaltubeasanexample.Thesingle-chipmicrocomputerneedstoprovidean8-bitsegmentcodeandan8-bitcode.Thus,weusuallychoosetwoofthefourparallelI/Oportsinthe51single-chipmicrocomputertoprovidesegmentcodesandbitcodesrespectively.Althoughthiscircuithardwareconnectionandsoftwareprogrammingarerelativelysimple,therearealsoproblems.Thatis:ToomanyI/Oportsareoccupied,whichaffectstheoveralluseofthemicrocontroller,andisnotconducivetotheaccessofotherdevices.Howtosolvethisproblem?Wecanuseatypeofshiftregisterforauxiliarycontrol.Here,thisblogusesthe74HC595chip.Figure1.74HC595CatalogIDescriptionIIIntroductionto74HC595III74HC595DisplayControlofMulti-digitDigitalTube3.1HardwareConnection3.2SoftwareProgramming3.3SimulationDebuggingIVConclusionFAQOrdering&QuantityIIIntroductionto74HC59574HC595isaCMOSshiftregisterwithopen-drainoutput.Theoutputportisacontrollablethree-stateoutput.Itcanalsocontrolthenext-levelcascadedchipserially.Itsstructureisusuallya16-pinDIPpackageorSOpackage.The74HC595pinoutisshowninFigure2,andthecorrespondingpinfunctionsareshowninTable1.Figure2.74HC595PinoutThemainfeaturesof74HC595are:8-bitserialinput/8-bitparallelorserialoutput;Three-stateoutputregister(three-stateoutput:agatecircuitwiththreeoutputstatesofhighlevel,lowlevelandhighimpedance);High-speedlow-powerconsumption,high-speedshiftclockfrequencyFmax25MHz.Table1.74HC595PinFunctionPinNumberPinNamePinFunction15,1~7Q0~Q7Paralleltri-stateoutputpin8GNDPowerground9Q7Serialdataoutputpin10/MRClearendofshiftregister(activelow)11SH_CPSerialdatainputclockline12ST_CPOutputmemorylatchclockline13/OEOutputenable(activelow)14DSSerialdatainputline16VCCPowerendIII74HC595DisplayControlofMulti-digitDigitalTubeHere,thisblogtakesthesingle-chipmicrocomputercontrolmulti-digitdigitaltubeasanexample.Tousethechipcorrectly,youmustfirstcorrectlyunderstandthetimingdiagramortruthtableofthechip.Thetruthtableof74HC595isshowninTable2.InputPinOutputPinDSSHCP/MRSTCP/OEHQ0~Q7outputhighimpedanceLQ0~Q7outputeffectivevalueLClearshiftregisterLRisingEdgeHShiftregisterstorelowlevelHRisingEdgeHShiftregisterstorehighlevelFallingEdgeHShiftregisterstateretentionRisingEdgeStatevalueinoutputshiftregisterFallingEdgeOutputmemorystateretentionItcanbefoundthattheserialdataisconnectedtotheDSpin,butitisonlyinputtotheshiftregisterwhenSH_CPisarisingedge,andentersthestorageregisterwhenST_CPisarisingedge.Ifthetwoclocksareconnectedtogether,theshiftregisterisalwaysonepulseearlierthanthestorageregister.Theshiftregisterhasaserialshiftinput(Ds),aserialoutput(Q7),andanasynchronouslow-levelreset.Thestorageregisterhasaparallel8-bit,three-statebusoutput.WhenOEisenabled(lowlevel),thedataofthestorageregisterisoutputtothebus.3.1HardwareConnectionSincethe8-bitdigitaltubeneedstoprovideatotalof16bitsofsegmentcodeandbitcodeatthesametime,itcannotberealizedbyusingone74HC595.Tosolvethisproblem,weusetwo595chipstocascadeseriallytoprovidean8-bitsegmentcode(providedbyU2)andan8-bitcode(providedbyU3).ThesimulationhardwarecircuitisshowninFigure3.Theinputsignalof595isconnectedtothethreeI/OportsofP2.0~P2.2respectively.Amongthem,P2.0providesserialinputsignals,P2.1andP2.2provideoutputandinputclocksignalsrespectively.Figure3.SimulationHardwareCircuitDiagram3.2SoftwareProgrammingHere,weuse2piecesof74HC595chipsforserialcascading.Therefore,youmustpayattentiontothesequenceofserialdataoutputwhenprogramming.Theusualpracticeisasfollows:First,writethedata(iebitcode)ofthe74HC595chipatthenextlevel;Then,writethedata(iesegmentcode)ofthefirst-level74HC595chip;Finally,releasetheparalleloutputpinstogetheratonce.Thesampleprogramisasfollows(partial):voidOneLed_Out(uchari,ucharLocation){ucharj;OutByte=Location;for(j=1;j=8;j++){DS=Bit_Out;SH_CP=0;SH_CP=1;SH_CP=0;OutByte=OutByte1;}OutByte=~Segment[i];for(j=1;j=8;j++){DS=Bit_Out;SH_CP=0;SH_CP=1;SH_CP=0;OutByte=OutByte1;}ST_CP=0;ST_CP=1;ST_CP=0;}3.3SimulationDebuggingWecandrawthehardwarecircuitdiagramontheProteus7platform,andthenwritethesoftwareprogramontheKeil4.0platformandcompileanddebugit.Then,loadthegeneratedHEXfileintothesimulationchipandrunthesimulation.Ifallgoeswell,theresultswillbedisplayedcorrectly.Accordingtothedisplayrequirements,itcanrealize8-bitdigitaltubeshiftdisplayor8-bitdigitaltubesimultaneousdisplay.ThesimulationresultsareshowninFigures4and5.Figure4.ShiftDisplayof8-bitDigitalTubeFigure5.SimultaneousDisplayof8-bitDigitalTubesIVConclusionThetestresultsofthisblogshowthattherearemanyadvantagestothedisplaycontrolofmulti-digitdigitaltubesthroughthecascadeof74HC595chips.Thesebenefitsaremainlyreflectedinthefollowingaspects:Itcangreatlyreducethedisplaycontrolofthesingle-chipdigitaltube;ItcangreatlyreducetheoccupancyoftheMCUI/Oportline;Thecircuitissimpleandeasytoprogram.Themethodintroducedinthisblog,whetheritistoconductsimulationteachingonacomputer,ortobuildactualhardwarecircuits.Ingeneral,Thecurrent74HC595chipiscost-effective,andthecostofbuildingacircuitislow,makingitverysuitableforgeneraluse.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.Whatisadigitaltube?Lightemittingdiodeconnectstheanodetogetherandthenconnectedtothepowerofpositiveiscalledcommonanodedigitaltube,lightemittingdiodeconnectedtothecathodeandthenconnectedtothepowerofthecathodeiscalledcommoncathodedigitaltube.Whatisthedifferencebetweenshiftregisterandcounter?Inashiftregister,theinputofelementNistheoutputofelementN-1,andallelementsusethesameclock.Inacounter,theinputofelementNistheinverseofitsoutput,andtheclockofelementN+1istheoutputofelementN.

VSLY5940-VISHAY

IDescriptionTheinstrumentationamplifiercircuithasthefollowingfeatures:HighInputImpedance;HighCommon-modeRejectionRatio;LowDrift;...Theabovefeaturesmakeitwidelyusedinfieldsofsmallsignalamplificationofsensoroutput.Thisblogwillintroduce4implementationoptionsofinstrumentationamplifiercircuits.These4optionsaredesignedbasedondifferentelectroniccomponents.Andtheyarealsoonthebasisofexplainingthecircuitstructureandprincipleoftheinstrumentamplifier.Theelectroniccomponentsdiscussedinthisbloginclude:LM741,OP07,LM324,AD620.Wewillsummarizefeaturesofthe4circuitthroughtesting,analysisandcomparison.Ibelievethisblogcanprovideacertainreferenceforcircuitdesignbeginners.WhatAreInstrumentationAmpilfiers?CatalogIDescriptionIIIntroduction2.1InstrumentationAmplifierOverview2.2InstrumentationAmplifierStuctureandPrincipleIIIInstrumentationAmplifierCircuitDesign3.1LM741CircuitOption3.2OP07CircuitOption3.3LM324CircuitOption3.4AD620CircuitOptionIVPerformanceTestandAnalysisFAQOrdering&QuantityIIIntroduction2.1InstrumentationAmplifierOverviewThesignalsinputbysmartmetersthroughsensorsgenerallyhavethecharacteristicsofsmallsignals:Thesignalamplitudeisverysmall(millivoltorevenmicrovoltmagnitude);Oftenaccompaniedbyloudnoise.Forsuchsignals,thefirststepofcircuitprocessingisusuallytoamplifysmallsignalswithaninstrumentationamplifier.Themainpurposeofamplificationisnottogain,buttoimprovethesignal-to-noiseratioofthecircuit.Atthesametime,fortheinstrumentationamplifiercircuit,thesmallertheinputsignalthatcanberesolved,thebetter;thewiderthedynamicrange,thebetter.Therefore,theperformanceoftheinstrumentationamplifiercircuitdirectlyaffectstherangeoftheinputsignalthatthesmartinstrumentcandetect.2.2InstrumentationAmplifierStuctureandPrincipleThetypicalstructureoftheinstrumentamplifiercircuitisshownasinFig.1.Itismainlycomposedoftwo-stagedifferentialamplifiercircuit.Figure1.StructureofInstrumentationAmplifierAmongthem,theoperationalamplifierA1,A2arein-phasedifferentialinputmodes.Non-invertinginputcangreatlyincreasetheinputimpedanceofthecircuit.Atthesametime,itcanalsoreducetheattenuationofweakinputsignalsbythecircuit;Differentialinputcanmakethecircuitonlyamplifythedifferentialmodesignal,andonlyfollowthecommonmodeinputsignal.Inthisway,theratiooftheamplitudeofthedifferentialmodesignaltothecommonmodesignal(ie,thecommonmoderejectionratioCMRR)senttothesubsequentstageisimproved.Inthisway,inthedifferentialamplifiercircuitcomposedofoperationalamplifierA3asthecorecomponent,undertheconditionthattheCMRRrequirementsremainunchanged,theaccuracymatchingrequirementsforresistorsR3andR4,RfandR5canbesignificantlyreduced.Asaresult,theinstrumentationamplifiercircuithasbettercommonmoderejectioncapabilitythanasimpledifferentialamplifiercircuit.UndertheconditionsofR1=R2,R3=R4,Rf=R5,thegainofthecircuitinFigure1is:G=(1+2R1/Rg)(Rf/R3)ItcanbeseenfromtheformulathattheadjustmentofthecircuitgaincanbeachievedbychangingtheRgresistance.IIIInstrumentationAmplifierCircuitDesignAtpresent,theimplementationmethodsofinstrumentationamplifiercircuitsaremainlydividedintotwocategories:Thefirstcategoryiscomposedofdiscretecomponents;Thesecondcategoryisdirectlyimplementedbyasingleintegratedchip.Intheblog,withsingleopampLM741andOP07,integratedfouropampLM324andmonolithicintegratedchipAD620asthemainelectroniccomponents,4kindsofinstrumentationamplifiercircuitoptionsaredesigned.3.1LM741CircuitOptionConsistsofthreegeneral-purposeoperationalamplifiersLM741toformathreeoperationalamplifierinstrumentamplifiercircuitform.Andsupplementedbyrelatedresistorperipheralcircuits.Atthesametime,addthebridgesignalinputcircuitofthenon-invertinginputterminalsofA1andA2,asshowninFigure2.Figure2.SingleOpAmpInstrumentationAmplifierA1~A3inFigure2canbereplacedwithLM741respectively.Theworkingprincipleofthecircuitisexactlythesameasthatofatypicalinstrumentationamplifiercircuit.3.2OP07CircuitOptionComposedof3precisionoperationalamplifiersOP07,thecircuitstructureandprinciplearethesameasinFig.2(3OP07sareusedtoreplaceA1~A3inFig.2respectively).3.3LM324CircuitOptionTakeafouroperationalamplifierintegratedcircuitLM324asthemaincomponent,asshowninFigure3.Itscharacteristicistointegrate4functionallyindependentoperationalamplifiersintothesameintegratedchip.WhataretheadvantagesofusingLM324?Thatis,itispossibletogreatlyreducethedifferenceindeviceperformanceofeachopampduetodifferentmanufacturingprocesses.Inaddition,theuseofaunifiedpowersupplyisconducivetothereductionofpowersupplynoiseandtheimprovementofcircuitperformanceindicators.Andthebasicworkingprincipleofthecircuitremainsunchanged.Figure3.LM324InstrumentationAmplifier3.4AD620CircuitOptionThecircuitconsistsofamonolithicintegratedchipAD620asthemainelectroniccomponents,asshowninFigure4.Itischaracterizedbyasimplecircuitstructure:anAD620,againsettingresistorRg,andaworkingpowersupply.Therefore,thedesignefficiencyisveryhigh.ThecircuitgaincalculationformulainFig.4is:G=49.4K/Rg+1.Figure4.AD620InstrumentationAmplifierIVPerformanceTestandAnalysisThefouroptionsoftheinstrumentationamplifiercircuitalladopttheformofabridgecircuitcomposedof4resistors,whichchangesthedouble-endeddifferentialinputintoasingle-endedsignalsourceinput.Theperformancetestismainlytocarryoutsimulationandactualcircuitperformancetestfromthefollowingaspects:1.ThemaximuminputofthesignalsourceVs;2.VsminimuminputofsignalsourceVs;3.Themaximumgainofthecircuit;4.Commonmoderejectionratio.ThetestdataareshowninTable1andTable2.Amongthem,themaximum(small)inputofVsreferstothemaximum(small)inputofthesignalsourcewhenthecircuitoutputisnotdistortedundergiventestconditions.Themaximumgainreferstothemaximumgainvalueofthecircuitthatcanbeachievedwhentheoutputisnotdistortedunderthegiventestconditions.ThecommonmoderejectionratioiscalculatedbytheformulaKCMRR=20|g|AVd/AVC|(dB).Note:fisthefrequencyofVsinputsignal;Thevoltagemeasurementdatainthetableareallexpressedbypeak-to-peakvalue;Duetothesimulationdevice,thesimulationofoption3withMultisimfailedintheexperiment,and-inTable1indicatesthefailuredata;Options1to4inthetablerespectivelyrepresenttheinstrumentationamplifiercircuitcomposedofLM741,OP07,LM324andAD620respectively.FromthemeasureddatainTable2,wecanseefromit:Foroption2,ithasthebestperformanceintermsofsignalinputrange(thatis,themaximumandminimuminputofVs),circuitgain,andcommon-moderejectionratio.Intermsofcomponentprice,itisalittlehigherthanthecostoftheLM741option1andtheLM324option3,butitismuchcheaperthantheAD620option4.Therefore,amongthefouroptions,option2ofOP07hasthehighestcostperformance.Foroption4,inadditiontoitsrelativelysmallmaximumgain,itsotherperformanceissecondonlytooption2.option4hastheadvantagesofsimplecircuit,superiorperformance,andsavingdesignspace.However,thehighcostisitsbiggestdisadvantage.Foroption1andoption3,thereislittledifferenceintheirperformance.option3isslightlybetterthanoption1,andtheyalsohaveabsolutepriceadvantages,buttheirperformanceisnotasgoodasoption2andoption4.Basedontheaboveanalysis,option2andoption4aresuitableforoccasionswithhigherperformancerequirementsforinstrumentamplifiercircuits.Amongthem:Option2ofOP07isthemostcost-effectiveOption4ofAD620issimpleandefficient,butthecostishigh.Option1ofLM741andOption3ofLM324aresuitableforoccasionswhereperformancerequirementsarenothighandcostsavingsareneeded.Accordingtospecificcircuitdesignrequirements,differentoptionsareselectedtoachieveoptimalresourceutilization.Figure5.InstrumentationAmplifierICInaddition,afterthecircuitdesignplanisdetermined,thefollowingaspectsshouldbepaidattentiontointhespecificcircuitdesignprocess:1.Payattentiontotheselectionofkeycomponents.Forexample,forthecircuitshowninFigure2,thereareafewthingstopayattentionto:MakethecharacteristicsofopampA1andA2asconsistentaspossible;Whenselectingresistors,resistorswithalowtemperaturecoefficientshouldbeusedtoobtainthelowestpossibledrift;TheselectionofR3,R4,R5andR6shouldmatchasmuchaspossible.2.Payattentiontoaddingvariousanti-interferencemeasuresinthecircuit.suchas:Thepowersupplydecouplingcapacitorshouldbeaddedatthelead-inendofthepowersupply;RClow-passfilteringshouldbeaddedtothesignalinputterminalorhigh-frequencynoisecancelingcapacitorsshouldbeaddedtothefeedbackloopoftheoperationalamplifierA1andA2;ThePCBdesignshouldbecarefullylaidoutandroutedreasonably,andgroundwiresshouldbehandledcorrectly.FAQWhatislm324?LM324isaQuadop-ampICintegratedwithfourop-ampspoweredbyacommonpowersupply.Thedifferentialinputvoltagerangecanbeequaltothatofpowersupplyvoltage....Generally,op-ampscanperformmathematicaloperations.Whichisthedifferencebetweenlm324andlm339?TheLM324hasacomplementaryoutputwhiletheLM339isopencollector.Inthecomplementaryoutput,currentcanflowineitherdirectionasrequired(eithersourceorsink)whiletheopencollectoroutputcanonlysinkcurrent.Whatisopampusefor?OperationalamplifiersarelineardevicesthathaveallthepropertiesrequiredfornearlyidealDCamplificationandarethereforeusedextensivelyinsignalconditioning,filteringortoperformmathematicaloperationssuchasadd,subtract,integrationanddifferentiation.Howdoesanopampwork?Whatislm324usedfor?LM324ICApplicationsTheapplicationsofICLM324includethefollowing.ByusingthisIC,theconventionalop-ampapplicationscanbeimplementedverysimply.ThisICcanbeusedasoscillators,rectifiers,amplifiers,comparatorsetc.

I.IntroductionAsweallknow,theionnitridingprocessrequiresrelativelyhighcontrolofthepressureinsidethefurnace,sothispaperdesignsagasflowcontrollerbasedontheL298NchipdrivenDCmotorcontrol,whichcanbeusedtocontrolthegasflowofthereactor.Soletsfirstunderstandtheionnitridingtheory.CatalogI.IntroductionII.IonNitridingTheoryIII.SystemFlowandPressureMeasurementandControlBlockDiagramIV.L298NChipIntroductionV.ControllerPrincipleVI.ConclusionFAQOrdering&QuantityII.IonNitridingTheoryNitridingisachemicalheattreatmentmethodtostrengthenthemetalsurface.Itistoplacemetalpartsinanactivenitrogenmedium,andatacertaintemperatureandholdingtime,thenitrogenelementcanpenetrateintothemetalsurface,therebychangingthechemicalcompositionofthemetallayertomakeithavehighwearresistance,fatiguestrength,corrosionresistanceandburnresistance,etc.,soitiswidelyusedinindustry.Ionnitridingiscarriedoutinalow-temperatureplasma.Thelow-pressuregasisionizedundertheactionofanelectricfieldtoproducehigh-energyionsandhigh-energyneutralatoms.Thesehigh-energyparticlescanimprovethestructureoftheinfiltrationlayer,promotethechemicalreactionprocess,andacceleratethenitridinglayerformation.Ionnitridingiscarriedoutinglowdischarge.Intheprocessofionnitriding,thepressurecontrolaccuracyofthefurnaceisrelativelyhigh,andthecontroldeviationreachesseveraltensofPa.AccordingtoPaschensLaw:Amongthem:Pisthegaspressure;Disthedistancebetweenparallelplateelectrodes;Visthecathodesecondaryelectronemissioncoefficient;BisStolevsconstant;Aisaconstant.Takingthederivativeofformula(1),thebreakdownvoltageexpression(2)canbeobtained:Itcanbeseenfromformula(2)thatthebreakdownvoltageVisrelatedtothegaspressureandd,andingeneralexperiments,disfixed,soionnitridingisextremelyimportantforpressurecontrol.III.SystemFlowandPressureMeasurementandControlBlockDiagramTheflowmetercontrolsthegasflowattheinlet.Whentheinletandexhaustflowsarebalanced,thefurnacepressureremainsstable.Duetotheinternalinfluenceoffurnacegasleakageandotherinterferencefactors,theinternalpressureofthefurnacefluctuatesupanddown,andthesystemdeviatesfromtheequilibriumstate,whichaffectstheplasmaprocessinseverecases.WeuseanordinaryDCmotortodrivetheDCmotorthroughtheL298N,andthemotordrivestheconetorotatethroughthereductionlever.Whentheconeisscrewedin,thegaspumpedoutperunittimeisreduced;whenitisscrewedout,thegaspumpedoutincreases,sothatthepressureinsidethefurnaceisstabilizedattherequiredvalue.Thechangeoffurnacepressureismeasuredbythepressuresensorandpassedthroughthetransmitter,whichsendsthegasflowcontrollertothefeedbackvoltage.Theelectricvacuumbutterflyvalveusedforthesuctionportisexpensive,asshowninFigure1.Figure1BlockdiagramofsystemflowandpressuremeasurementandcontrolIV.L298NChipIntroductionL298NcanacceptstandardTTLlogiclevelsignalVSS,andVSScanbeconnectedto4.5~7Vvoltage.4pinVSisconnectedtothepowersupplyvoltage,andtheVSvoltagerangeVIHis+2.5~46V.Theoutputcurrentcanreach2.5A,whichcandriveinductiveloads.Theemittersofpin1andpin15areseparatelyledouttoconnectthecurrentsamplingresistortoformacurrentsensingsignal.L298candrivetwomotors,OUT1,OUT2andOUT3,OUT4canbeconnectedtoeachmotor,thisexperimentaldevicewechoosetodriveonemotor.Pins5,7,10and12areconnectedtotheinputcontrolleveltocontroltheforwardandreverserotationofthemotor.EnAandEnBareconnectedtothecontrolpotentialenergyendtocontrolthestallingofthemotor.Figure2istheL298Nfunctionallogicdiagram,Table1istheL298Ninternalfuntionalmodule.Figure2L298NfunctionallogicdiagramEnAIn1In2OperativeCondition0Stop110Rotatingforward101Inversion111Brake100StopTable1L298NinternalfunctionalmoduleThefunctionalmoduleofIn3andIn4isthesameasTable1.ItcanbeseenfromTable1thatwhenEnAislowlevel,theinputlevelhasaneffectonmotorcontrol.WhenEnAishighlevel,whenEnAishigh,theinputlevelisonehighandonelow,andthemotorrotatesforwardorreverse.Iftheyarebothlowlevel,themotorwillstop,andiftheyarebothhighlevel,themotorwillbrake.V.ControllerPrincipleFigure3istheschematicdiagramofthecontroller,composedof3dashedblockdiagrams:Figure3TheschematicdiagramofthecontrollerThefollowingarethefunctionsofthe3dashedblockdiagrams:(1)Thedashedblockdiagram1controlstheforwardandreverserotationofthemotor,U1AandU2Aarecomparators,andVIcomesfromthevoltageofthefurnacepressuresensor.WhenVIVRBF1,U1Aoutputshighlevel,U2Aoutputhighlevelturnsintolowlevelthroughinverter,andthemotorrotatesforward.Similarly,whenVIVRBF1,themotorreverses.Theforwardandreverserotationofthemotorcancontroltheflowofgasextractedbytheairextractor,therebychangingthepressureinsidethefurnace.(2)Inthedashedblockdiagram2,twocomparatorsU3AandU4Aformadual-limitcomparator.WhenVBVIVA,itoutputslowlevel,andwhenVIVA,VIVB,itoutputshighlevel.VA,VBaretheupperandlowerlimitsofthevoltageconvertedbythefurnacepressuretransducer,thatis,thecontrolrangeofthereactionfurnacepressure.Accordingtoprocessrequirements,wecanspecifythevaluesofVAandVBbyourselves,aslongasthefurnacepressureiswithintherangedeterminedbyVAandVB,themotorstops(notethatVB<VRBF1<VA,ifitisnotinthisrange,thesystemisunstable).(3)Thedashedblockdiagram3isalongdelaycircuit.U5Aisacomparator,Rs1isthesamplingresistor,VRBF2isthemotorovercurrentvoltage.ThevoltageonRs1isgreaterthanVREF2,themotorisovercurrent,andU5Aoutputslowlevel.Itcanbeseenfromtheabovethatblock1controlstheforwardandreverserotationofthemotor,andblock2controlsthesizeoftherippleofthefurnacepressure.Whenthefurnacepressureistoosmallortoolarge,themotorturnstoafixedpositionatbothendstostop,accordingtothesteady-stateoperatingequationoftheDCmotor:Amongthem:Фisthemagneticfluxofeachpoleofthemotor;Ceistheelectromotiveforceconstant;Nisthenumberofmotorrevolutions;Iaisthearmaturecurrent;Raisthearmatureloopresistance.WhenthenumberofrevolutionsofthemotorNis0,thecurrentofthemotorincreasessharply,andthemotorwillburnoutifthetimeistoolong.Butwhenthemotorstarts,thecurrentinthecoilinthemotoralsoincreasessharply,sowemustseparatethesetwostates.Thelongdelaycircuitcandistinguishthesetwostates.Theworkingprincipleofthelong-delaycircuit:WhentheRs1overcurrentU5Ageneratesanegativepulseandisdifferentiated,thepulsetriggerspin2of555,thecircuitisset,andpin3outputshighlevel.Becausethedischargeterminal7pinisopen,C1,R5andU6Aformedasanintegration,thenstartworking,thechargingvoltageonthecapacitorC1riseslinearly,andtheintegrationconstantofthedelayoperationalamplifieris100R5C1.WhenthechargingvoltageonC1,thatis,thevoltageonpin6exceeds2/3VCC,the555circuitresetsandoutputsalowlevel.Themotorgenerallystart-upinlessthan0.8s,andtheC1chargingtimeisgenerally0.8~1s.TheoutputlevelofU5AisORedwiththeoutputlevelofpin3of555viaU7.IftheoutputlowlevelofU5AislongerthanthechargingtimeofC1,U7outputslowlevelafterC1ischarged.TheANDgateU8inputstothe6pinENAterminalofL298N.Themotorstops.IftheoutputlevelofU5AislessthanthechargingtimeofC1,pin6willnotactandthemotorwillstartnormally.Thelongdelaycircuitabsorbsthemotorstart-upovercurrentvoltagewaveform,sothatthemotorstartsnormally.VI.ConclusionThisarticlesummarizesthedesignschemeforthepressurecontrolofionnitridingbasedontheL298Nchip.Ithasbeenprovedthattheuseofthiscontrollertocontrolthegasflowcanreduceproductioncosts,increasethesystemcostperformance,andimprovethecontroldynamicperformanceandstabilityoftheentiresystemcontrol.FAQWhatisl298n?ThisL298NMotorDriverModuleisahighpowermotordrivermodulefordrivingDCandStepperMotors.ThismoduleconsistsofanL298motordriverICanda78M055Vregulator.L298NModulecancontrolupto4DCmotors,or2DCmotorswithdirectionalandspeedcontrol.Whatistheuseofl298n?TheL298NisadualH-BridgemotordriverwhichallowsspeedanddirectioncontroloftwoDCmotorsatthesametime.ThemodulecandriveDCmotorsthathavevoltagesbetween5and35V,withapeakcurrentupto2A.Howdoesl298ncontrolDCmotorspeed?1.IfyousendaHIGHsignaltotheenable1pin,motorAisreadytobecontrolledandatthemaximumspeed;2.IfyousendaLOWsignaltotheenable1pin,motorAturnsoff;3.IfyousendaPWMsignal,youcancontrolthespeedofthemotor.Themotorspeedisproportionaltothedutycycle.Whatisl298nmotordrivermodule?ThisL298NMotorDriverModuleisahighpowermotordrivermodulefordrivingDCandStepperMotors.ThismoduleconsistsofanL298motordriverICanda78M055Vregulator.L298NModulecancontrolupto4DCmotors,or2DCmotorswithdirectionalandspeedcontrol.Howdoesl298nmotordriverwork?TheL298NisadualH-BridgemotordriverwhichallowsspeedanddirectioncontroloftwoDCmotorsatthesametime.ThemodulecandriveDCmotorsthathavevoltagesbetween5and35V,withapeakcurrentupto2A.Howdoiuseal298motordriverwithArduino?Startbyconnectingpowersupplytothemotors.InourexperimentweareusingDCGearboxMotors(alsoknownasTTmotors)thatareusuallyfoundintwo-wheel-driverobots.Theyareratedfor3to12V.So,wewillconnectexternal12VpowersupplytotheVCCterminal.WhatisthefunctionofHbridge?AnH-bridgeisanelectroniccircuitthatswitchesthepolarityofavoltageappliedtoaload.ThesecircuitsareoftenusedinroboticsandotherapplicationstoallowDCmotorstorunforwardsorbackwards.Whatisthedifferencebetweenl293dandl298n?L293isquadruplehalf-HdriverwhileL298isdualfull-Hdriver,i.e,inL293allfourinput-outputlinesareindependentwhileinL298,ahalfHdrivercannotbeusedindependently,onlyfullHdriverhastobeused....Hence,heatsinkisprovidedinL298.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.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.DescriptionBC327isageneralpurposePNPtransistor,todaywewilldiscussaboutitspinoutconfiguration,equivalent,uses,packagedimensionsandmanyotherdetails.BC327UsingTransistorsBC327BC337toMakeaMiniPowerfulAudioAmplifierCatalogueDescriptionBC327IntroductionBC327PinConfigurationBC327MarkingDiagramBC327TechnicalSpecificationsBC327CADModelsBC327ApplicationsBC327PackageDimensionsBC327FunctionalEquivalentsBC327PopularitybyRegionWhereandHowtoUseBC327HowtoGetLongTermPerformancefromBC327BC327ManufacturerComponentDatasheetOrdering&QuantityBC327IntroductionBC327isageneralpurposePNPBJPtransistorthatcanbeusedforswitchingandamplificationpurposesinelectroniccircuits.Thetransistorfeatures800mAcollectorcurrenthenceitcanbeusedtodrivevarietyofloadsinanelectronicapplication.Themaxcollector-emittervoltageis-45Vthereforeitcaneasilyhandleloadvoltageunder45V.Apartfromthattransistoralsofeatures625mWcollectordissipationandDCcurrentgainofmaximum630thereforeitcanalsobeusedasanaudioamplifierorforanytypeofsignalamplification.BC327manufacturedindifferenthFEclassificationthatcanbedifferentiatewiththecodenumberwrittenafterthetransistornumber.Ifyoufindcode-16afterthetransistornumberthenthehFEwillbe100~250,ifthecodeis-25thenthehFEwillbe160~400andifthecodeis-40thenthehFEwillbe250~630.BC327PinConfigurationPinNumberPinNameDescription1CollectorCurrentflowsinthroughcollector,normallyconnectedtoload2BaseControlsthebiasingoftransistor,UsedtoturnONorOFFthetransistor3EmitterCurrentDrainsoutthroughemitter,normallyconnectedtogroundBC327MarkingDiagramBC327TechnicalSpecificationsPackageType:TO-92TransistorType:PNPMaxCollectorCurrent(IC):-800mAMaxCollector-EmitterVoltage(VCE):-45VMaxCollector-BaseVoltage(VCB):-50VMaxEmitter-BaseVoltage(VBE):-5VMaxCollectorDissipation(Pc):625MilliwattMaxTransitionFrequency(fT):100MHzMinimumMaximumDCCurrentGain(hFE):100to630MaxStorageOperatingtemperatureShouldbe:-55to+150CentigradeBC327CADModelsBC327PartSymbolBC327FootprintBC327ApplicationsOutputofMicrocontrollerstoDriveLoadsAnyTypeofSignalAmplificationAudioamplifierAudioAmpStagesDriveLoadsUnder800mABC327PackageDimensionsBC327FunctionalEquivalentsBC327PopularitybyRegionWhereandHowtoUseBC327LikeotheressentialgeneralpurposetransistorstheBC327isalsoamustofhavetransistorinyourlabbecauseitcanbeusedinwidevarietyofapplications.Itcanbeusedasaswitchtodriveloadsupto800mAwhichincludeshighpowerrelays,highpowertransistors,highpowerLEDs,ICsandotherpartsofacircuit.With-5Vemitter-basevoltagethistransistorcanalsobeusedastheoutputofmicrocontrollerstodriveloadofupto800mAwhichcaneasilydrivemotors,modules,sensorsetc.HowtoGetLongTermPerformancefromBC327Togetlongtermgoodperformancewiththistransistorinyourelectronicapplicationsitisrecommendedtonotdriveloadmorethan0.8Aor800mA,donotdriveloadormorethan-45V,alwaysuseasuitablebaseresistorwiththetransistor.Donotstoreoroperatethistransistorintemperaturebelow-55centigradeandabove+150centigradeandalwayscheckpinconfigurationbeforeplacinginthecircuit.BC327ManufacturerONSemiconductor(Nasdaq:ON)isdrivingenergyefficientinnovations,empoweringcustomerstoreduceglobalenergyuse.Thecompanyoffersacomprehensiveportfolioofenergyefficientpowerandsignalmanagement,logic,discreteandcustomsolutionstohelpdesignengineerssolvetheiruniquedesignchallengesinautomotive,communications,computing,consumer,industrial,LEDlighting,medical,military/aerospaceandpowersupplyapplications.ONSemiconductoroperatesaresponsive,reliable,world-classsupplychainandqualityprogram,andanetworkofmanufacturingfacilities,salesofficesanddesigncentersinkeymarketsthroughoutNorthAmerica,Europe,andtheAsiaPacificregions.ComponentDatasheetBC327Datasheet

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