Tkool Electronics

A base resistor limits the extra amount of current going into the base of the transistor.

TPS54331

A base resistor limits the extra amount of current going into the base of the transistor.

IIntroductionThisblogmainlydiscussesthedifferencebetweenLM324andLM324A,andwhethertheycanreplaceeachotherinthecircuit.DifferencebetweenLM324andothermodelslikeLM741,LM358,LM324N,etc.arealsodiscussedinthisblog.Figure1.LM324CatalogIIntroductionIILM324ADandLM3242.1Difference2.2Parameters2.3CantheTwoReplaceEachOther?IIIDifferenceBetweenLM324andLM741,LM358IVDifferenceBetweenLM324andLM318VDifferenceBetweenLM324andLM324NVIDifferenceBetweenLM324andLM324JFAQOrderingQuantityIILM324ADandLM324LM324isafour-operationalamplifier,whichisalargecategory.Itincludestwoindependent,high-gain,internalfrequency-compensatedoperationalamplifiers.LM324issuitableforsinglepowersupplywithawiderangeofpowersupplyvoltages,andisalsosuitablefordualpowersupplyoperatingmode.Undertherecommendedoperatingconditions,thepowersupplycurrentisindependentofthepowersupplyvoltage.AccordingtothesuffixofLM324,Aseedmodel(specification)isincluded.Thefollowingwillintroducetoyouthedifferencebetweenlm324Aandlm324,andwhethertheycanbeusedinterchangeablyinthecircuit.2.1DifferenceTheaccuracyindexofLM324AisslightlyhigherthanthatofLM324.TakeTIsproductsasanexample:OffsetVoltageTheinputoffsetvoltageoftheLM324Ais2mV(typical)to3mV(maximum);TheinputoffsetvoltageoftheLM324is3mV(typical)to7mV(maximum).OffsetCurrentTheinputoffsetcurrentoftheLM324Ais2nA(typical)to30nA(maximum);TheinputoffsetcurrentoftheLM324is2nA(typical)to50nA(maximum).InputBiasCurrentTheinputbiascurrentofLM324Ais-15nA(typical)~-100nA(maximum);TheinputbiascurrentofLM324is-20nA(typical)~-250nA(maximum).Figure2.Parameters2.2ParametersInfact,whetheritistheNseriesortheAseriesoftheLM324,theybelongtothesub-seriesoftheLM324.Onlyindividualparameterssuchasinputoffsetvoltageandinputoffsetcurrentareslightlydifferent,andtheotherparametersarethesame.ParameterLM324ALM324ArchitectureBipolarBipolarCMRR(Typ)(dB)8080FeaturesStandardAmpsStandardAmpsGBW(Typ)(MHz)1.21.2Inputbiascurrent(Max)(pA)100000250000Iqperchannel(Typ)(mA)0.1750.175Numberofchannels(#)44Offsetdrift(Typ)(uV/C)7-Operatingtemperaturerange(C)0to700to70Outputcurrent(Typ)(mA)4040Rail-to-railIntoV-IntoV-RatingCatalogCatalogSlewrate(Typ)(V/us)0.50.5Totalsupplyvoltage(Max)(+5V=5,+/-5V=10)3232Totalsupplyvoltage(Min)(+5V=5,+/-5V=10)33Vnat1kHz(Typ)(nV/rtHz)3535Vos(offsetvoltage@25C)(Max)(mV)372.3CantheTwoReplaceEachOther?Whendiscussingwhetherthetwochipscanbereplacedwitheachother,wegenerallyrefertothefollowingsituations:SameFunction,SamePackageThetwoareinterchangeable.Forexample,asfarasthecommonlyusedchipsLM741,LM324,LM339areconcerned,therearemanymanufacturerswhosechipspecificationsaremoreorlessthesame,thepackageisthesame,andthepinfunctionisalsothesame.SameFunction,DifferentPackageBothcanbereplaced.However,thesizeandshapearedifferent,soitcannotbeinstalleddirectlyintheoriginalposition,suchasdualin-linepackageandfour-sidedflatpackage.DifferentFunction,SamePackageThetwocannotbeinterchanged.Because,packagingistheproductsexternalspecifications.Forexample,the74ls373latchand74ls374flip-flopcannotbesimplyinterchanged.BecausetheLM324andLM324ADhavethesamefunction,butdifferentpackages,theycanbereplaced.However,thisisonlylimitedtothesimulationcircuit.Ifitistheactualcircuit,duetothedifferentpackaging,youoriginallyexpectedthatthesolderingpositionmaynotreachthesize,soyouneedtoreplacethecircuit.Figure3.LM324AIIIDifferenceBetweenLM324andLM741,LM358Thesethreetypesofopampsareallgeneralpurposeopamps,andtheirperformanceindicatorsarenotveryhigh.Thespecificdifferencesaremainlyreflectedinthefollowingaspects:NumberofChannelsLM741:singleopamp;LM358:dualopamp;LM324:quadopamp.WorkingVoltageRangeLM741:7V~36V;LM358:3V~32V;LM324:3V~32V.UnityGainBandwidthLM741:1MHzLM358:700kHzLM324:1MHzPrecisionTheinputoffsetvoltageofthesethreetypesofopampsare:LM741:6mV(maximum);LM358:7mV;LM324:7mV.InputImpedanceTheLM741andLM358arelower,andtheinputbiascurrentisintheAlevel,whiletheLM324is90nA,whichisdozensoftimeshigherthantheprevioustwo.Figure4.LM741IVDifferenceBetweenLM324andLM318TheLM324isageneral-purposeopamp(quadopamps).Itsslewrateis0.4V/usandthegain-bandwidthproductis1.3MHz,whichissuitableforgeneraluse.LM318isahigh-speedoperationalamplifier(singleopamp),itsslewrateis50V/us,andthegain-bandwidthproductis15MHz.Therefore,LM318issuitableforamplifyingsignalswithhigherfrequenciesissuitableforamplifyingsignalswithhigherfrequencies.Figure5.LM318VDifferenceBetweenLM324andLM324NLM324hasthesamefunctionasLM324N.ThedifferencebetweenthetwoisthattheLM324doesnotspecifythepackageform,andtheLM324Npackageisaplasticdualin-linepackage.Figure6.LM324NP.S.Nsuffixreferstothepackaging:NisDIPMisSOICMTisTSSOPJisceramicDIPVIDifferenceBetweenLM324andLM324JLM324JisaDIPpackageofLM324producedbyNS,whichisitselfLM324.AnotherpackageformofLM324producedbyNSisLM324M,andthepackageisSO8.Sincedifferentmanufacturershavedifferentsuffixstandards,youneedtoseethedatasheetgivenbythecertainmanufacturer.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.IDescriptionThisblogwillintroduce8simpleandeasytounderstandcircuitsthatusingTL431asthemaincomponent.SuchasTL431PrecisionReferenceVoltageCircuits,TL431AdjustableRegulatedPowerSupplyCircuit,etc.HopethisblogcanhelpbeginnerstobetterunderstandTL431ShuntRegualtor.ElectronicsTutorial-TheTL431Part1/3-GettingtoknowthecomponentIDescriptionIITL431PrecisionReferenceVoltageSourceIIITL431AdjustableRegulatedPowerSupplyIVTL431OvervoltageProtectionCircuitVTL431ConstantCurrentSourceCircuitVITL431ComparatorVIITL431VoltageMonitorVIIITL431ControllableShuntCharacteristicsIXTL431SwitchingPowerSupplyComponentDatasheetFAQOrderingQuantityIITL431PrecisionReferenceVoltageSourceTheprecisionreferencevoltagesourcecircuithasgoodtemperaturestabilityandlargeoutputcurrent.Butwhenconnectingcapacitiveloads,weshouldpayattentiontothevalueofCLtoavoidself-excitation.Figure1.TL431Circuit:PrecisionReferenceVoltageSourceIIITL431AdjustableRegulatedPowerSupplyAsshowninthefigure,Vocanbeadjustedbetween2.5~36V.V0=Vref(1+R1/R2)(Vref=2.5v).Sincethewithstandvoltageisrelatedto(Vi-Vo),whenthevoltagedifferenceislarge,thepowerconsumptionofRincreases.Figure2.TL431Circuit:AdjustableRegulatedPowerSupplyIVTL431OvervoltageProtectionCircuitAsshowninthefigure,whenViexceedsacertainvoltage,TL431triggers.Atthistime,thethyristoristurnedonandgeneratesalargeinstantaneouscurrent,whichblowsthefuse,therebyprotectingtherearcircuit.Vprotectionpoint=(1+R1/R2)Vref.Figure3.TL431Circuit:OvervoltageProtectionVTL431ConstantCurrentSourceCircuitAsthepictureshows.TheconstantcurrentvalueisrelatedtoVrefandtheexternalresistance,andthemarginshouldbeconsideredwhenselectingthepowertransistor.Thisconstantcurrentsourcecanbeusedasacurrentlimiterifitisconnectedtoastabilizedcircuit.Figure4.TL431Circuit:ConstantCurrentSourceVITL431ComparatorAsshowninthefigure,itcleverlyusesthecriticalvoltageofVref=2.5v.DuetothesmallinternalresistanceoftheTL431,theinputandoutputwaveformstrackwell.Figure5.TL431Circuit:ComparatorVIITL431VoltageMonitorAsshowninthefigure,usethetransfercharacteristicsofTL431toformapracticalvoltagemonitor.Whenthevoltageisbetweentheupperandlowerlimitvoltages,theLEDpowerandupperandlowerlimitvoltagesare(1+R1/R2)Vrefand(1+R3/R4)Vrefrespectively.Figure6.TL431Circuit:VoltageMonitorVIIITL431ControllableShuntCharacteristicsItcanbeseenfromthefunctionalmodulediagramofTL431thatwhenthevoltageattheREFterminalchangesslightly,theshuntfromthecathodetotheanodewillchangewithin1-100mA.Withthiscontrollableshuntfeature,smallvoltagechangescanbeusedtocontrolrelays,indicatorlights,etc.,andevendirectlydriveaudiocurrentloads.Thepictureshowsasimple400mWmonopoweramplifiercircuitforthisapplication.Figure7.TL431Circuit:ControllableShuntCharacteristicsIXTL431SwitchingPowerSupplyInthepastordinaryswitchingpowersupplydesign,theoutputvoltageisusuallyfedbackdirectlytotheinputterminalaftererroramplification.Thisvoltagecontrolmodecanalsoworkwellinsomeapplications.However,withthedevelopmentoftechnology,mostoftheworldspowersupplymanufacturingindustryhasadoptedaschemewithasimilartopology.Theswitchingpowersupplyofthiskindofstructurehasthefollowingcharacteristics:TheoutputisfedbackbyTL431(controllableshuntreference)andtheerrorisamplified.ThesinkingendofTL431drivesthelight-emittingpartofanoptocoupler.ThefeedbackvoltageobtainedbythephotosensitivepartofthephotocoupleronthemainsideofthepowersupplyisusedtoadjusttheswitchingtimeofacurrentmodePWMcontroller.Thus,astableDCvoltageoutputisobtained.Figure8.TL431Circuit:SwitchingPowerSupplyThepictureaboveisapractical4Wswitchtype5VDCregulatedpowersupplycircuit.ThiscircuitadoptsthiskindoftopologicalstructureandusesTOPSwitchtechnologyatthesametime.Inthepicture:C1,L1,C8andC9constituteanEMIfilter;BR1andC2rectifyandfiltertheinputACvoltage;D1andD2areusedtoeliminatethespikevoltagecausedbytransformerleakageinductance;U1isacurrentmodePWMcontrollerchipwithbuilt-inMOSFET,whichacceptsfeedbackandcontrolstheoperationoftheentirecircuit;D3andC3arethesub-polerectifierfiltercircuit;L2andC4formalow-passfiltertoreducetheoutputripplevoltage;R2andR3areoutputsamplingresistors,andthedividedvoltageoftheoutputiscontrolledbytheREFterminalofTL431tocontroltheshuntofthedevicefromthecathodetotheanode.Thiscurrentdirectlydrivesthelight-emittingpartoftheoptocouplerU2.Thenwhentheoutputvoltagehasatendencytoincrease,theVrefwillincreaseandthecurrentflowingthroughtheTL431willincrease.Therefore,thelight-emittingoftheoptocouplerisstrengthened,andthefeedbackvoltageobtainedbythephotosensitiveterminalisalsogreater.U1willchangetheswitchingtimeoftheMOSFETafterreceivingthisincreasedfeedbackvoltage,andtheoutputvoltagewilldropwiththechange.Infact,theprocessdescribedabovewillreachequilibriuminaveryshorttime.Whenbalanced,Vref=2.5V,andR2=R3,sotheoutputisstable5V.Itshouldbenotedherethattheoutputvoltagecannolongerbechangedbysimplychangingthevalues​​ofthesamplingresistorsR2andR3.Because,theparameterofeachcomponentintheswitchingpowersupplywillhaveagreatinfluenceontheworkingstateofthewholecircuit.Accordingtotheparametersshowninthefigure:Thecircuitcanbewithintheinputrangeof90VAC~264VAC(50/60Hz);Output+5V;Theaccuracyisbetterthan3%;Theoutputpoweris4W;Themaximumoutputcurrentcanreach0.8A;Thetypicalconversionefficiencyis70%.ComponentDatasheetTL431DatasheetFAQWhatistheUseofTL431?TheTL431isaProgrammablePrecisionReferenceandiscommonlyusedinswitchingpowersupplies,whereitprovidesfeedbackindicatingiftheoutputvoltageistoohighortoolow.Byusingaspecialcircuitcalledabandgap,theTL431providesastablevoltagereferenceacrossawidetemperaturerange.WhatisTL431Transistor?TheTL431isaRegulatorDiodewhoseoutputvoltagecanbeprogrammedbychangingthevalueofresistorsconnectedtoit.ItactsalmostlikeaZenerdiodeexceptforthatthevoltageratingofthisICisprogrammable.Itiscommonlyusedtoprovidenegativeorpositivevoltagereferences.HowdoesaShuntRegulatorWork?TheShuntRegulatororShuntVoltageRegulatorisaformofvoltageregulatorwheretheregulatingelementshuntsthecurrenttoground.Theshuntregulatoroperatesbymaintainingaconstantvoltageacrossitsterminalsandittakesupthesurpluscurrenttomaintainthevoltageacrosstheload.

TPS54331

IIntroduction1.1WhatisLM324?LM324isalow-costquad-operationalamplifier.Thelow-frequencysignalgeneratordesignedwithitasthecoredevicehastheadvantagesofsimplecircuit,stablewaveform,economicalandpractical,andeasytouse.Itcanoutputthesinewave,squarewaveandtrianglewavesignalscommonlyusedinexperimentaltesting.Andthefrequencyandamplitudeofthesignalcanbeadjusted.Figure1.LM324Quad-OperationalAmplifiers1.2WhatisWaveGenerator?Thewavegeneratorreferstoaninstrumentthatgenerateselectricaltestsignalswiththerequiredparameters.Thecircuitformcanbecomposedofop-ampsanddiscretecomponents,orasingle-chipintegratedfunctiongenerator.Itiswidelyusedinproductionpracticeandtechnology.Somestandardproductsthatarewidelyusedatpresent,althoughtheyhavecompletefunctionsandhigh-performanceindicators,aremoreexpensiveandhavemanyfunctionsthatarenotavailable.1.3WaveGeneratorUsingLM324Inthisblog,quad-operationalamplifierswithdifferentialinputLM324areusedasthecoredevice,asinewaveisgeneratedbyanRCbridgeoscillationcircuit,thenasquarewaveisgeneratedbyazero-crossingcomparator,andatriangularwaveisgeneratedbyanintegratingcircuit.ThroughProteussoftwaresimulationandsimulationexperiment,theidealwaveformof20Hz~20kHzisobtained,andthefrequencyandamplitudeofthesignalcanbeadjusted.CatalogIIntroduction1.1WhatisLM324?1.2WhatisWaveGenerator?1.3WaveGeneratorUsingLM324IIHowtoGenerateandTransformWaveIIIDesignofUnitCircuit3.1SineWaveGeneratingCircuit3.2SquareWaveGeneratingCircuit3.3TriangleWaveGeneratingCircuitIVCircuitSimulationandTestFAQOrderingQuantityIIHowtoGenerateandTransformWaveTherearemanyschemesforwaveformgenerationandtransformation.Here,thesinewavesquarewavetrianglewaveschemeshowninFigure2isused.Amongthem,thesinewaveisgeneratedbytheRCbridgeoscillationcircuit,whichischaracterizedbystableamplitudeandfrequencyandeasyadjustment,andcangenerateasinesignalwithaverylowfrequency;thenazero-crossingcomparatorisusedtogenerateasquarewave,andthenanRCintegrationcircuitisusedtogenerateatriangularwave.Thissignalhasthesamefrequency.Thiscircuithasasimplestructureandcanproducegoodsineandsquarewavesignals,butitisdifficulttogenerateasynchronizedtriangularwavesignalthroughanintegrationcircuit.Thereasonisthatifthetimeconstantoftheintegrationcircuitdoesnotchange,theamplitudeoftheoutputtrianglewavechangesatthesametimeasthefrequencyofthesquarewavesignalchanges.Tokeepthetrianglewaveoutputamplitudeunchangedandgoodlinearity,theintegrationtimeconstantmustbechangedatthesametime.Figure2.WaveGenerationandTransformationThefrequencyofthesignalisdeterminedbytheRCfrequencyselectionnetworkofthesinusoidaloscillationcircuit.Duetothelargefrequencyrange,thefrequencyselectionnetworkusesthreesetsofcapacitorswithdifferentcapacitiestoformthreefrequencybands,whichareselectedbythebandswitch,andthenthecoaxialpotentiometeradjuststheoscillationfrequency.Threekindsofwaveformscanbeselectedthroughagearswitch,andthenoutputindependentlythroughtheamplitudeadjustmentpotentiometertoachievethepurposeofsignalselectionandamplitudeadjustment.IIIDesignofUnitCircuit3.1SineWaveGeneratingCircuitThesinewavegeneratingcircuitshouldnotonlygeneratethesinesignaloftherequiredoutput,butalsotheinputsignalofthefollowingcircuit.ThispartofthecircuitusesatypicalRCbridgesinewaveoscillationcircuit,asshowninFigure3,itconsistsoftwopartsoftheamplificationlinkandfrequencyselectionnetwork.Theoperationalamplifieristhecoretoformtheamplificationlink.ThenetworkcomposedofresistorR1andcapacitorC1inseries,resistorR2andcapacitorC2inparallelistheRCseries-parallelfrequencyselectionnetwork.Thefrequencyselectionnetworkisalsoapositivefeedbackcircuit,providingzerophaseshiftandforminganin-phaseamplifier.R3andR4aredeepnegativefeedbackstoobtainagoodoutputwaveform.IfR1=R2=R,C1=C2=C,thenthecenterfrequencyofthefrequencyselectionnetworkisf0=1/(2RC).Whenthecircuitworksatthisfrequency,thefeedbackcoefficientisthelargestandis|F|max=1/3.Accordingtotheoscillationconditions,thevoltagegainoftheamplifiercircuitshouldbeatleast3A|(R4+R3)/R4|.Therefore,inordertoensuretheoscillationofthecircuit,R32R4isrequired.Figure3.RCBridgeOscillationCircuitInpracticalapplications,inordertoadjustthefrequencyandthegainoftheamplifier,thecircuitshowninFigure4canbeused.Amongthem:R3~R5anddiodesD1,D2formanegativefeedbacknetworkandamplitudestabilizationlink.AdjustingRV3canchangethefeedbackcoefficientofnegativefeedback,therebyadjustingthevoltagegainoftheamplifiercircuittomeetthereplicationconditionsofoscillation.Figure4.RCOscillationSimulationCircuitInviewofthelargespanofthesignalfrequencyfrom20Hzto20kHz,twogroupsofthreecapacitorseachwithacapacityof10timesdifferentandtwocoaxialpotentiometersareusedforadjustment.Choosedifferentcapacitorsasthecoarseadjustmentoftheoscillationfrequencyf0,andusethecoaxialpotentiometertoachievethefineadjustmentoff0.Theresistancevaluescorrespondingtodifferentcapacitancesandoscillationfrequenciesf0areshowninTable1.Table1.CorrespondencebetweenOscillationFrequencyf0andResistanceCapacitanceItcanbeseenfromTable1thateachcombinationofcapacitanceandresistancecanadjustacertainrangeoffrequencies,andthesethreerangeshaveintersections,sothefrequencycanbecontinuouslyadjusted.Ifyouwanttogeneratea200Hzto2kHzsignal,youcansetthecapacitorto33nF,andthenadjustRV1andRV2tomaketheresistanceinserieswithR1andR2changebetween24kand2.4k.3.2SquareWaveGeneratingCircuitThesquarewavegeneratingcircuitisrelativelysimple.TheinvertinginputoftheoperationalamplifierLM324isgrounded.Thenon-invertinginputisconnectedtotheoutputofthesinewavegeneratingcircuittoformazero-crossingcomparator,asshowninFigure5.Figure5.SquareWaveGeneratingCircuitWhentheinputsinusoidalsignalsinchangesbetweenpositiveandnegativehalfcycles,theoutputisasquarewavesignalsquwithafixedamplitudeandinphasewiththesinewave.3.3TriangleWaveGeneratingCircuitThetriangularwavegeneratingcircuitadoptstheRCintegratingcircuitshowninFigure6,whichiscomposedoftheoperationalamplifierU1:C,C3/C3/C3,R7andRV4.Figure6.TriangleWaveGeneratingCircuitThesquarewavesignalsquisconnectedtotheinvertinginputterminaloftheamplifierthroughR7andRV4,andtheoutputsignalisthetriangularwavetriigeneratedbytheintegraltransformationoftheRCcircuitcomposedofR7,RV4andC3/C3/C3.C3,C3,C3areselectedbythebandswitch(thisswitchshouldbesynchronizedwiththebandswitchoftheselectedfrequencynetwork)tochangetheintegraltimeconstantofthecircuitindifferentfrequencybands.PotentiometerRV4canadjusttheamplitudeoftheoutputsignal.Inordertoobtainatriangularwavewithgoodlinearity,resistorR8isusedfornegativefeedbacklimiting,andwhenselectingthecomponentparameters,thetimeconstantoftheintegratingcircuit=RCshouldbegreaterthanhalftheperiodofthesquarewavesignal(thewidthofthesquarewave).Ifthesignalfrequencyis100Hz,thewidthofthesquarewaveis0.005s.IfC=1F,thenR5k.IVCircuitSimulationandTestDraweachpartofthecircuitshowninFigure4toFigure6inProteus.ThethreepartsofthecircuitareconnectedaccordingtotherelationshipshowninFigure2.Thenconnecttheoutputofeachpartofthecircuittothevirtualoscilloscopeandthenstartthesimulation.YoucanobservesimulationwaveforminFigure7.Inthesimulationprocess,thereareseveralissuesthatneedtobenoted:Accordingtotheoreticalcalculations,thesinewavegenerationcircuitcanstarttovibratewhentheamplifiergainisgreaterthan3,butsometimesthephenomenonofnovibrationoccursintheactualsimulationprocess.Disturbanceisaddedtosolveit,asshowninFigure4,-9Vpowersupply,seetheliteraturefordetails.Tochangethefrequencyband,thethreegroupsofcapacitorsC1/C1/C1,C2/C2/C2,C3/C3/C3mustbechangedatthesametime,otherwisetherewillbenovibrationorThewaveformisdistorted.PotentiometersRV1andRV2shouldbeadjustedtothesameresistance.AdjustRV3tomaketheoutputsinewaveamplitudereachthemaximumundistortedstate.RV4canadjusttheamplitudeoftheoutputtrianglewave.Throughexperimentaltestingofthecircuit,inThreeidealwaveformscanbeobservedontheoscilloscope.Itshouldbenotedthat:switchesSW1,SW2,andSW3shouldusea3-positionswitchwithmorethan3groups.RV1,RV2usecoaxialpotentiometersforadjustment.Theoutputsignalcanbeoutputinparallelatthesametime,oritcanbeoutputseparatelythroughapotentiometer(tomakethesignalamplitudeadjustable)throughaselectionswitch.Inaddition,thepowersupplydoesnotneedtobedisturbedduringactualtesting.Figure7.SimulationWaveformObtainedinProteusFAQWhatislm324?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.Afterreadingthisblog,doyouhaveabetterunderstandingofLM324?IfyouhaveanythoughtsaboutLM324,pleasedonthesitatetoletusknowinthecommentssection!HowtocheckifTL431isbroken?IfTL431isreallybroken,thenhowtoreplaceit?Thesetwokindsofproblemswillbediscussedinthisblog.HowtoTESTTL431VoltageReference/TL431ATL432KIA431ShuntRegulatorCircuitCatalogIIntroduction1.1WhatisTL431?1.2TL431PinoutIIHowtoMeasureTL431?IIIHowtoTestTL431?IVTL431ReplaceableModelsVConclusionComponentDatasheetFAQIIntroduction1.1WhatisTL431?TL431isa2.5~36VAdjustableShuntRegulator.Withitsexcellentperformanceandlowprice,itcanbewidelyusedinsingle-chipprecisionswitchingpowersuppliesorprecisionlinearregulatedpowersupplies.Inaddition,TL431canalsoformavoltagecomparator,powersupplyvoltagemonitor,delaycircuit,precisionconstantcurrentsource,etc.1.2TL431PinoutThesymbolofTL431isshownintheFigure1.IthasthreepolesA,G,andKrespectively(markedA,K,Ronsomeschematicdiagrams).AandKarethepositiveandnegativeterminalsoftheZenerdiode,andtheGpoleisthesamplingterminal.Figure1.TL431Pinout(1)HowtodetermineAandKpolesAccordingtotheschematicdiagram,theAandKpolescanbejudgedbymeasuringthediodewithamultimeter.Whenmeasuring,settherangetoRX1Kgear.WhentheblackpenisconnectedtotheApoleandtheredpenisconnectedtotheKpole,theresistanceisinaconductingstate(theresistanceofacommonsilicondiode).Inaddition,interchangethetestleads,iftheresistanceisinfinite,thepinconnectedtotheblackpenistheApole,andtheotherpinistheKpole.(2)HowtodetermineGpoleSetthemultimetersrangetoRx10k,connecttheblackpentotheKpole,andtheredpentotheApole.Atthistime,themetershouldhavenoindication.WhentouchingtheblackpenwithonehandandtheGpolewiththeotherhand,thepointershouldswinggreatly.Whenthisconditionismet,thepintouchedbythehandistheGpole.IIHowtoMeasureTL431?(1)MeasurementofforwardandreverseresistanceofzenerdiodeThemultimeterrangeissettoRxlk,theblackpenisconnectedtoApole,andtheredpenisconnectedtoKpole.Atthistime,theforwardresistanceoftheZenerdiodeismeasured.Tomeasurethereverseresistanceelbow,therangeshouldbesettoRxlk.ThedatameasuredwiththeMF47meteris:theforwardresistanceis6xlk,andthereverseresistanceshouldbeinfinite.(2)MeasurementoftheforwardandreverseresistanceofGpoleandAandKpolesThemultimeterrangeissettoRxlk,theblackpenisconnectedtotheGpole,andtheredpenisconnectedtotheApole.Theresistanceshouldbe35xlk.Theresistanceofinterchangeabletestleadsshouldbe10xlkn.ConnecttheblackpentotheGpoleandtheredpentotheKpole.Theresistanceshouldbe11lk.Ifthetestleadsareinterchanged,theresistanceshouldbeinfinite.(3)MeasurementoftheforwardandreverseresistanceofKpoleandA,GpoleThemultimeterrangeissettoRxlk,theblackpenisconnectedtotheKpole,andtheredpenisconnectedtotheGpole.Atthistime,theresistanceisinfinite.Exchangethetestleads,theresistanceshouldbe11lk.ConnecttheblackpentotheKpoleandtheredpentotheApole,andtheresistanceshouldbeinfinite.Ifthetestleadsareinterchanged,theresistanceis8xlk.Figure2.TL431IIIHowtoTestTL431?AsshowninthefigureisthecircuittestedbyTL431.Forthepowersupply,itisa0~20Vmaintenancepowersupply.WeconnectedanammeterbetweentheKpoleandthepowersupply.ThisisdoneinordertoclearlyobservethechangesinthecurrentoftheKpoleasthevoltageoftheGpolechanges.WealsoconnectavoltmeterbetweenKandA.Inthisway,wecanclearlyobservethechangesintheoutputoftheTL431withthepowersupply.Beforethetest,adjustthepotentiometertonearthemiddlevalue.Then,useadigitalmetertomeasuretheKpole-to-groundvoltageandadjustthevoltageoutputofthemaintenancepowersupply.Atthistime,itcanbefoundthatthevoltagebetweentheKpoleandthegroundhasonlytwostates:oneisabout2V(lowlevel);theotherisequaltothepowersupplyvoltage(highlevel).Figure3.TL431CircuitThenhowtojudgewhetherTL431isnormal?Fortheon-lineTL431powersupplyerrorcomparator,theexternalmaintenancepowersupplycanbeusedtodetect.ConnectthemaintenancepowersupplytothesamplingpointoftheTL431,andwhenthevoltageishigherthanthenominalvoltage,theTL431willbeturnedonandtheK-polevoltagewillbelow.Thatistosay,whenthepowersupplyvoltageincreases,theTL431isturnedon,sothatthediodeofthephotocoupleristurnedon,sothatthetransistorisinasaturatedstate,andtheturn-ontimeoftheprimarypowerswitchisfinallyshortened(reducingthedutycycle).Inthisway,theoutputvoltageisreduced.Ifthemaintenancevoltageisreduced,theTL431willbecutoff,theKpolevoltagewillbehigh,andthediodeofthephotocouplerwillbecutoff,whichwillmaketheTriodeinthecut-offstate,andfinallycontroltheincreaseoftheturn-ontimeoftheprimarypowerswitchofthetransformer(increasethedutycycle).Increasetheoutputvoltage.Theclosed-loopvoltagestabilizingcircuitoftheswitchingpowersupplyusestheTL431onorofftwostatestoadjustthedutycycleoftheswitchtocontrolthestabilityoftheoutputvoltage.Whenmeasuringthemultimeter,iftheresistancebetweenthepolesofthelCisnormal,theTL431canbejudgedtobenormal.Whenusingthemaintenancepowersupplypower-ontest,inthecaseofchangingthepowersupplyvoltage,iftheTL431poletothegroundhastwochangesofhighandlowlevels,theTL431canbejudgedtobenormal.Figure4.TL431ShuntRegulatorICIVTL431ReplaceableModelsWhenTL431isdamaged,ifthereisnoreplacementofthesamemodel,itcanbedirectlyreplacedwithKA431,A431,LM431,YL431,S431,etc.TL431suffixlettersindicateproductlevelandoperatingtemperaturerange.Ciscommercialproduct(-10℃~+70℃);Iisanindustrialproduct(-40℃~+85℃);Mismilitaryproduct(-55℃~+125℃).VConclusionInsummary,itistheintroductionofHowtoTestTL431anditsReplacement.TL431hasawiderangeofapplications.Itcanbeusedasaprecisionreferencevoltagesource,andcanalsobeusedtoreplacearegulatortubetoformaparalleladjustableregulatedpowersupply.Itcanalsobeusedasaconstantcurrentsourceandvoltagedetectioncircuit.Inaddition,intheswitchingpowersupply,TL431canalsobeusedasasimpleerroramplifier.ComponentDatasheetTL431DatasheetFAQWhatistheUseofTL431?TheTL431isaProgrammablePrecisionReferenceandiscommonlyusedinswitchingpowersupplies,whereitprovidesfeedbackindicatingiftheoutputvoltageistoohighortoolow.Byusingaspecialcircuitcalledabandgap,theTL431providesastablevoltagereferenceacrossawidetemperaturerange.WhatisTL431Transistor?TheTL431isaRegulatorDiodewhoseoutputvoltagecanbeprogrammedbychangingthevalueofresistorsconnectedtoit.ItactsalmostlikeaZenerdiodeexceptforthatthevoltageratingofthisICisprogrammable.Itiscommonlyusedtoprovidenegativeorpositivevoltagereferences.HowdoesaShuntRegulatorWork?TheShuntRegulatororShuntVoltageRegulatorisaformofvoltageregulatorwheretheregulatingelementshuntsthecurrenttoground.Theshuntregulatoroperatesbymaintainingaconstantvoltageacrossitsterminalsandittakesupthesurpluscurrenttomaintainthevoltageacrosstheload.WhatisLP2951?TheLP2951isabipolar,low-dropoutvoltageregulator.TheLP2951regulatorisusuallyusedinapplicationsthatrequireapresetoutputvoltage,whichcanbeeasilyconfiguredusingtworesistors.Thisdevicecanprovidelowdropoutregulationinawiderangeofoutputvoltagerangingfrom1.235Vto30V.Therefore,ithasbecomeapopularchoiceformicrocircuitsthatrequiremicropowerregulatorsthatcanprovideupto100mAloadcurrent.ThisblogprovidesyouwithabasicoverviewoftheLP2951voltageregulator,includingitspindescriptions,functionsandspecifications,alternativeproducts,etc.,tohelpyouquicklyunderstandwhatLP2951is.CatalogLP2951PinoutLP2951CircuitLP2951ApplicationsLP2951FeaturesLP2951CAD/CAEsymbolsLP2951FunctionalBlockDiagramLP2951AdvantageLP2951PackageLP2951SpecificationLP2951ManufacturerLP2951DocumentsWheretouseLP2951ComponentDatasheetLP2951PinoutPinNAMEPinNumberTYPEDESCRIPTIONERROR5OActive-lowopen-collectorerroroutput.GoeslowwhenVOUTdropsby6%ofitsnominalvalue.FEEDBACK7IDeterminestheoutputvoltage.ConnecttoVTAP(withOUTPUTtiedtoSENSE)tooutputthefixedvoltagecorrespondingtothepartversion,orconnecttoaresistordividertoadjusttheoutputvoltage.GND4GroundINPUT8ISupplyinputOUTPUT1OVoltageoutput.SENSE2ISensestheoutputvoltage.ConnecttoOUTPUT(withFEEDBACKtiedtoVTAP)tooutputthevoltagecorrespondingtothepartversion.SHUTDOWN3IActive-highinput.Shutsdownthedevice.VTAP6OTietoFEEDBACKtooutputthefixedvoltagecorrespondingtothepartversion.LP2951CircuitLP2951Circuit1:12-Vto5-VConverterLP2951Circuit2LP2951Circuit3LP2951Circuit4:RegulatorwithEarlyWarningandAuxiliaryOutputLP2951ApplicationsApplicationswithHigh-VoltageInputPowerSuppliesLP2951FeaturesWideInputRange:Upto30VRatedOutputCurrentof100mALowDropout:380mV(Typ)at100mALowQuiescentCurrent:75A(Typ)TightLineRegulation:0.03%(Typ)TightLoadRegulation:0.04%(Typ)HighVOAccuracy1.4%at25C2%OverTemperatureCanBeUsedasaRegulatororReferenceStableWithLowESR(12m)CapacitorsCurrent-andThermal-LimitingFeaturesLP2950Only(3-Pin)Fixed-OutputVoltagesof5V,3.3V,and3VLP2951Only(8-PinPackage)Fixed-orAdjustable-OutputVoltages:5V/ADJ,3.3V/ADJ,and3V/ADJLow-VoltageErrorSignalonFallingOutputShutdownCapabilityRemoteSenseCapabilityforOptimalOutputRegulationandAccuracyLP2951CAD/CAEsymbolsPackagePinsDownloadSOIC(D)8ViewoptionsSON(DRG)8ViewoptionsLP2951FunctionalBlockDiagramLP2951AdvantageLP2951voltageregulatorTheLP2950andLP2951devicesarebipolar,low-dropoutvoltageregulatorsthatcanaccommodateawideinputsupply-voltagerangeofupto30V.Theeasy-to-use,3-pinLP2950isavailableinfixed-outputvoltagesof5V,3.3V,and3V.However,the8-pinLP2951deviceisabletooutputeitherafixedoradjustableoutputfromthesamedevice.BytyingtheOUTPUTandSENSEpinstogether,andtheFEEDBACKandVTAPpinstogether,theLP2951deviceoutputsafixed5V,3.3V,or3V(dependingontheversion).Alternatively,byleavingtheSENSEandVTAPpinsopenandconnectingFEEDBACKtoanexternalresistordivider,theoutputcanbesettoanyvaluebetween1.235Vto30V.The8-pinLP2951devicealsooffersadditionalfunctionalitythatmakesitparticularlysuitableforbattery-poweredapplications.Forexample,alogic-compatibleshutdownfeatureallowstheregulatortobeputinstandbymodeforpowersavings.Inaddition,thereisabuilt-insupervisorresetfunctioninwhichtheERRORoutputgoeslowwhenVOUTdropsby6%ofitsnominalvalueforwhateverreasonsduetoadropinVIN,currentlimiting,orthermalshutdown.TheLP2950andLP2951devicesaredesignedtominimizeallerrorcontributionstotheoutputvoltage.Withatightoutputtolerance(0.5%at25C),averylowoutputvoltagetemperaturecoefficient(20ppmtypical),extremelygoodlineandloadregulation(0.3%and0.4%typical),andremotesensingcapability,thepartscanbeusedaseitherlow-powervoltagereferencesor100-mAregulators.LP2951PackagePARTNUMBERPACKAGEBODYSIZE(NOM)LP2951SOIC(8)4.90mmx3.90mmSON(8)3.00mmx3.00mmLP2951SpecificationOutputoptionsAdjustableOutput,FixedOutputIout(Max)(A)0.1Vin(Max)(V)30Vin(Min)(V)2Vout(Max)(V)29Vout(Min)(V)1.2Fixedoutputoptions(V)3,3.3,5Noise(uVrms)160Iq(Typ)(mA)0.075ThermalresistanceJA(C/W)52Loadcapacitance(Min)(F)1RatingCatalogRegulatedoutputs(#)1FeaturesEnable,PowerGoodAccuracy(%)3PSRR@100KHz(dB)57Dropoutvoltage(Vdo)(Typ)(mV)380Operatingtemperaturerange(C)-40to125LP2951ManufacturerTexasInstrumentsInc.(TI)isanAmericantechnologycompanythatdesignsandmanufacturessemiconductorsandvariousintegratedcircuits,whichitsellstoelectronicsdesignersandmanufacturersglobally.ItsheadquartersareinDallas,Texas,UnitedStates.TIisoneofthetoptensemiconductorcompaniesworldwide,basedonsalesvolume.TexasInstrumentssfocusisondevelopinganalogchipsandembeddedprocessors,whichaccountsformorethan80%oftheirrevenue.TIalsoproducesTIdigitallightprocessing(DLP)technologyandeducationtechnologyproductsincludingcalculators,microcontrollersandmulti-coreprocessors.Todate,TIhasmorethan43,000patentsworldwide.LP2951DocumentsUserguideLP2951EVMUsersGuide(Rev.A)ApplicationnoteESR,Stability,andtheLDORegulator(Rev.A)TechnicalarticleLDObasics:capacitorvs.capacitanceWheretouseLP2951BothLP2950andLP2951featurelowquiescentcurrentandlowdropoutvoltage(typical50mVatlightloadand380mVat100mA).Thesedevicesareanexcellentchoiceforuseinbatterypoweredapplicationsuchascordlesstelephones,radiocontrolsystemsandportablecomputers.ComponentDatasheetLP2951Datasheet

TPS54331

TheNE555timerICisanintegratedcircuit(chip)usedinavarietyoftimer,delay,pulsegeneration,andoscillatorapplications.ThisblogprovidesyouwithabasicoverviewoftheNE555TimerIC,includingitspindescriptions,functionsandspecifications,alternativeproducts,etc.,tohelpyouquicklyunderstandwhatNE555is.Wewillbegladtofindthatthisblogcanbeusefulforpeoplelovingelectroniccomponents😊Howa555TimerICWorks?CatalogNE555PinoutNE555FeaturesNE555AdvantageNE555CircuitNE555ParametersNE555PackageNE555CAD/CAEsymbolsNE555ManufacturerComponentDatasheetFAQNE555PinoutThepinoutofthe8-pinNE555timerand14-pin556dualtimerareshowninthefollowingtable.Sincethe556isconceptuallytwo555timersthatsharepowerpins,thepinnumbersforeachhalfissplitacrosstwocolumns.Inthefollowingtable,longerpinnamesareused,becausemanufacturersneverstandardizedtheabbreviatedpinnamesacrossalldatasheets.PinNo.PinNamePinDirectionPinDescription1GNDPowerGroundsupply:thispinisthegroundreferencevoltage(zerovolts).2TRIGGERInputTrigger:whenthevoltageatthispinfallsbelow​12ofthevoltageofCONTROL(​13VCC,exceptwhenCONTROLisdrivenbyanexternalsignal),theOUTPUTgoestothehighstateandatimingintervalstarts.Aslongasthispincontinuestobekeptatalowvoltage,theOUTPUTwillremaininthehighstate.3OUTPUTOutputOutput:thispinisapush-pull(P.P.)outputthatisdriventoeitheralowstate(GND)orahighstate(forbipolartimers,VCCminusapproximately1.7volts)(forCMOStimers,VCC).Forbipolartimers,thispincandriveupto200mA,butCMOStimersareabletodriveless(variesbychip).Forbipolartimers,ifthispindrivesanedge-sensitiveinputofadigitallogicchip,a100to1000pFdecouplingcapacitor(betweenthispinandGND)mayneedtobeaddedtopreventdoubletriggering.4RESETInputReset:atimingintervalmayberesetbydrivingthispintoGND,butthetimingdoesnotbeginagainuntilthispinrisesaboveapproximately0.7volts.ThispinoverridesTRIGGER,whichinturnoverridesTHRESHOLD.Ifthispinisnotused,itshouldbeconnectedtoVCCtopreventelectricalnoiseaccidentallycausingareset.5CONTROLInputControl:thispinprovidesaccesstotheinternalvoltagedivider(​23VCCbydefault).Byapplyingavoltagetothispin,thetimingcharacteristicscanbechanged.Inastablemode,thispincanbeusedtofrequency-modulatetheOUTPUTstate.Ifthispinisnotused,itshouldbeconnectedtoa10nFdecouplingcapacitor(betweenthispinandGND)toensureelectricalnoisedoesntaffecttheinternalvoltagedivider.6THRESHOLDInputThreshold:whenthevoltageatthispinisgreaterthanthevoltageatCONTROL(​23VCCexceptwhenCONTROLisdrivenbyanexternalsignal),thentheOUTPUThighstatetimingintervalends,causingtheOUTPUTtogotothelowstate.7DISCHARGEOutputDischarge:Forbipolartimers,thispinisanopen-collector(O.C.)output,CMOStimersareopen-drain(O.D.).Thispincanbeusedtodischargeacapacitorbetweenintervals,inphasewiththeOUTPUT.Inbistablemodeandschmitttriggermode,thispinisunused,whichallowsittobeusedasanalternateoutput.8VCCPowerPositivesupply:Forbipolartimers,thevoltagerangeistypically4.5to16volts,somearespecedforupto18volts,thoughmostwilloperateaslowas3volts.ForCMOStimers,thevoltagerangeistypically2to15volts,somearespecedforupto18volts,andsomearespecedaslowas1volt.Seethesupplyminandmaxcolumnsinthederivativestableinthisarticle.Decouplingcapacitor(s)aregenerallyapplied(betweenthispinandGND)asagoodpractice.NE555FeaturesTimingFromMicrosecondstoHoursAstableorMonostableOperationAdjustableDutyCycleTTL-CompatibleOutputCanSinkorSourceUpto200mAOnProductsComplianttoMIL-PRF-38535,AllParametersAreTestedUnlessOtherwiseNoted.OnAllOtherProducts,ProductionProcessingDoesNotNecessarilyIncludeTestingofAllParameters.NE555AdvantageNE555TimerICThesedevicesareprecisiontimingcircuitscapableofproducingaccuratetimedelaysoroscillation.Inthetime-delayormono-stablemodeofoperation,thetimedintervaliscontrolledbyasingleexternalresistorandcapacitornetwork.Inthea-stablemodeofoperation,thefrequencyanddutycyclecanbecontrolledindependentlywithtwoexternalresistorsandasingleexternalcapacitor.Thethresholdandtriggerlevelsnormallyaretwo-thirdsandone-third,respectively,ofVCC.Theselevelscanbealteredbyuseofthecontrol-voltageterminal.Whenthetriggerinputfallsbelowthetriggerlevel,theflip-flopisset,andtheoutputgoeshigh.Ifthetriggerinputisabovethetriggerlevelandthethresholdinputisabovethethresholdlevel,theflip-flopisresetandtheoutputislow.Thereset(RESET)inputcanoverrideallotherinputsandcanbeusedtoinitiateanewtimingcycle.WhenRESETgoeslow,theflip-flopisreset,andtheoutputgoeslow.Whentheoutputislow,alow-impedancepathisprovidedbetweendischarge(DISCH)andground.Theoutputcircuitiscapableofsinkingorsourcingcurrentupto200mA.Operationisspecifiedforsuppliesof5Vto15V.Witha5-Vsupply,outputlevelsarecompatiblewithTTLinputs.NE555CircuitMissing-PulseDetectorPulse-WidthModulationPulse-PositionModulationSequentialTimerNE555ParametersVCC(Min)(V)4.5VCC(Max)(V)16Iq(Typ)(uA)2000RatingCatalogOperatingtemperaturerange(C)0to70NE555PackagePackagePinsSizePDIP(P)893mm9.81x9.43SOIC(D)819mm3.91x4.9SOIC(D)819mm4.9x3.9SOP(PS)848mm6.2x7.8TSSOP(PW)819mm3x6.4NE555CAD/CAEsymbolsPackagePinsDownloadPDIP(P)8ViewoptionsSO(PS)8ViewoptionsSOIC(D)8ViewoptionsTSSOP(PW)8ViewoptionsNE555ManufacturerTexasInstrumentsInc.(TI)isanAmericantechnologycompanythatdesignsandmanufacturessemiconductorsandvariousintegratedcircuits,whichitsellstoelectronicsdesignersandmanufacturersglobally.ItsheadquartersareinDallas,Texas,UnitedStates.TIisoneofthetoptensemiconductorcompaniesworldwide,basedonsalesvolume.TexasInstrumentssfocusisondevelopinganalogchipsandembeddedprocessors,whichaccountsformorethan80%oftheirrevenue.TIalsoproducesTIdigitallightprocessing(DLP)technologyandeducationtechnologyproductsincludingcalculators,microcontrollersandmulti-coreprocessors.Todate,TIhasmorethan43,000patentsworldwide.ComponentDatasheetNE555DatasheetFAQWhatdoesa555timerdo?The555timerICisaverycheap,popularandusefulprecisiontimingdevicewhichcanactaseitherasimpletimertogeneratesinglepulsesorlongtimedelays,orasarelaxationoscillatorproducingastringofstabilisedwaveformsofvaryingdutycyclesfrom50to100%.HowdoIknowifmyICisne555?HowtoCheckthe555TimerIC?Firstofall,inserttheICinsocket(ifused)verycarefullysothatnopinof555timergetsdamage.Nowtoseetheresult,switchonthepowersupply.Ifyour555timerisworkingproperly,thenboththeLEDs(RedLEDsinmycase)willglowalternately.Areall555timersthesame?Overall,mostbipolar555chipsareeitheridenticalorverycloselyrelatedtoeachother,thoughsomehaveminordesigndifferences.ThereismorevariationsbetweentheCMOS555chips,becauseofthepushtowardsredesignsthatworkatloweroperatingvoltageandlowerstandbycurrent.Howdoyoutriggera555?UsuallythetimerIC555istriggeredbyapplyinganegativegoingpulsetoitstriggerpin2.Thistimeristriggeredthroughapositivepulseinitsresetpin.InthemonostablemodeIC555startstimingcyclewhenanegativepulseisappliedtoitstriggerpin2.Howdoyouusea555chip?Usejumperwiretoconnectpins4and8toeachother(red)andpins2and6toeachother(yellow).Attachthepositiveleadofaspeakertopin3ofthe555andconnectthenegativeleadtoground(pin1).LowvaluesofRAshouldbeavoidedbecausetheypreventthe555timerfromdischargingthecapacitorCnormally.Howdoyouusea555timer?Witha555timer,wecanproduceclocksignalsofvaryingfrequenciesbasedonthevaluesoftheexternalresistorsandcapacitorthatwechoose.Wecanproduceclocksignalsofanyfrequencyneeded.A1Hzclocksignalwillcycleonceeverysecond.A2Hzclocksignalwillcycleevery0.5seconds.2N3904isaTransistor.Thisblogcovers2N3904Transistorpinout,datasheet,equivalent,circuitandotherinformationonhowtouseandwheretousethisdevice.PlayingwithTransistors:NPN2N3904TransistorExperimentCatalog2N3904CADModel2N3904Pinout2N3904Circuit2N3904Applications2N3904Features2N3904Advantage2N3904Working2N3904Package2N3904Parameters2N3904Manufacturer2N3904Documents2N3904EnvironmentalandExportClassifications2N3904Equivalents2N3904ProductCompliance2N3904PopularitybyRegion2N3904asAmplifier2N3904asSwitchWhereandHowtouse2N3904HowtoSafelyLongRun2N3904inaCircuitComponentDatasheetFAQOrderingQuantity2N3904CADModel2N3904Symbol2N3904Footprint2N3904PinoutPinNumberPinNameDescription1EmitterCurrentDrainsoutthroughemitter2BaseControlsthebiasingoftransistor3CollectorCurrentflowsinthroughcollector2N3904CircuitDelayandRiseTimeEquivalentTestCircuitStorageandFallTimeEquivalentTestCircuit2N3904ApplicationsSensorCircuitsAudioPreamplifiersAudioAmplifierStagesDarlingtonPairs2N3904FeaturesBi-PolarNPNTransistorDCCurrentGain(hFE)is300maximumContinuousCollectorcurrent(IC)is200mABase-EmitterVoltage(VBE)is6VCollector-EmitterVoltage(VCE)is40VCollector-BaseVoltage(VCB)is60VAvailableinTo-92Package2N3904Advantage2N3904Transistor2N3904isawidelyusedgeneralpurposetransistor.Itismostlyusedbyelectronicstudentsandhobbyistsintheirprojects,butitisalsousedincommercialelectronicproducts.Itcanbeusedinwidevarietyofelectronicapplicationsforswitchingandamplificationpurposes.Themaximumcollectorcurrentofthetransistoris200mAthereforeusercandriveloadsunder200mAintheirelectronicapplications,Moreover2N3904alsoworkgoodasanamplifier,thetotaldevicedissipationis625milliwattduetowhichitcanalsobeusedforaudioandRFsignalamplificationpurposes.2N3904Working2N3904has3layersiniti.e.singlePdopedlayerembeddedbetweentwoNdopedlayers.These3layersaredifferentfromeachotherintermsofsizeandconcentrationofdoping.ThecentredlayerisverysmallinsizeandislowconcentratedascomparedtotheothertwoNdopedlayers.Collectorlayerisbiggerinsizethantheothertwolayersandthushighlydoped.AsmallcurrentonthePdopedlayertransformsintoahighercurrentonothertwoterminals.2N3904Package2N3904StraightLead2N3904BentLead2N3904ParametersCategoryDiscreteSemiconductorProductsTransistors-Bipolar(BJT)-SingleMfrONSemiconductorSeries-PackageTrayPartStatusObsoleteTransistorTypeNPNVceSaturation(Max)@Ib,Ic300mV@5mA,50mACurrent-CollectorCutoff(Max)50nADCCurrentGain(hFE)(Min)@Ic,Vce100@10mA,1VFrequencyTransition300MHzOperatingTemperature-55C~150C(TJ)MountingTypeThroughHolePackage/CaseTO-226-3,TO-92-3(TO-226AA)Current-Collector(Ic)(Max)200mAVoltage-CollectorEmitterBreakdown(Max)40VPowerMax625mWManufacturerONSemiconductorProductCategoryBipolarTransistorsBJTMountingStyleThroughHolePackage/CaseTO-92-3TransistorPolarityNPNConfigurationSingleCollector-EmitterVoltageVCEOMax40VCollector-BaseVoltageVCBO60VEmitter-BaseVoltageVEBO6VCollector-EmitterSaturationVoltage0.3VMaximumDCCollectorCurrent0.2APd-PowerDissipation625MwGainBandwidthProductfT270MHzMinimumOperatingTemperature-65CMaximumOperatingTemperature+150CHeight5.33mmLength5.2mmTechnologySiWidth4.19mmBrandONSemiconductorContinuousCollectorCurrent0.2ADCCollector/BaseGainhfeMin60ProductTypeBJTs-BipolarTransistorsSubcategoryTransistorsBJTs-BipolarTransistors2N3904ManufacturerONSemiconductor(Nasdaq:ON)isdrivingenergyefficientinnovations,empoweringcustomerstoreduceglobalenergyuse.Thecompanyoffersacomprehensiveportfolioofenergyefficientpowerandsignalmanagement,logic,discreteandcustomsolutionstohelpdesignengineerssolvetheiruniquedesignchallengesinautomotive,communications,computing,consumer,industrial,LEDlighting,medical,military/aerospaceandpowersupplyapplications.ONSemiconductoroperatesaresponsive,reliable,world-classsupplychainandqualityprogram,andanetworkofmanufacturingfacilities,salesofficesanddesigncentersinkeymarketsthroughoutNorthAmerica,Europe,andtheAsiaPacificregions.2N3904DocumentsGeneralAnnouncement-2DBarcoding(PDF)Processchangenotification(PDF)Processchangenotification(PDF)2N3904EnvironmentalandExportClassificationsAttributeDescriptionRoHSStatusRoHSnon-compliant2N3904Equivalents2N2222,S8050,2N4401,BC537,SS9013(Pinconfigurationofsometransistorsmaydifferentfrom2N3904thereforecheckpinconfigurationbeforereplacinginacircuit)2N3904ProductComplianceUSHTS8541210095CAHTS8541210000CNHTS8541210000TARIC8541210000ECCNEAR992N3904PopularitybyRegion2N3904asAmplifierATransistorsactsasanAmplifierwhenoperatinginActiveRegion.Itcanamplifypower,voltageandcurrentatdifferentconfigurations.Someoftheconfigurationsusedinamplifiercircuitsare1.Commonemitteramplifier2.Commoncollectoramplifier3.CommonbaseamplifierOftheabovetypescommonemittertypeisthepopularandmostlyusedconfiguration.WhenusesasanAmplifiertheDCcurrentgainoftheTransistorcanbecalculatedbyusingthebelowformulaeDCCurrentGain=CollectorCurrent(IC)/BaseCurrent(IB)2N3904asSwitchWhenatransistorisusedasaswitchitisoperatedintheSaturationandCut-OffRegionasexplainedabove.AsdiscussedatransistorwillactasanOpenswitchduringForwardBiasandasaclosedswitchduringReverseBias,thisbiasingcanbeachievedbysupplyingtherequiredamountofcurrenttothebasepin.Asmentionedthebiasingcurrentshouldmaximumof5mA.Anythingmorethan5mAwillkilltheTransistor;hencearesistorisalwaysaddedinserieswithbasepin.Thevalueofthisresistor(RB)canbecalculatedusingbelowformulae.RB=VBE/IBWhere,thevalueofVBEshouldbe5Vfor2N3904andtheBasecurrent(IBdependsontheCollectorcurrent(IC).ThevalueofIBshouldnotexceedmA.WhereandHowtouse2N39042N3904Transistor2N3904canbeusedinanyelectronicapplicationswhichfallunderitselectricalcharacteristics,letsupposeifyouwanttoswitchaloadinanelectronicapplicationthatrequirescurrentunder200mAthenthistransistorwillworkquitewellandyoucandrivevarietyofloadswiththistransistorforexamplerelays,highpowertransistors,LEDs,aportionofanelectroniccircuitetc.Whenusingasanamplifieritcanbeusedinaudioamplificationstages,asanamplifiertodrivesmallspeakers,asanaudiopreamplifieranditcanalsobeusedinamplificationstagesofRFapplications.HowtoSafelyLongRun2N3904inaCircuitTogetgoodandlongtermperformancefromthistransistoritissuggestedtonotdriveloadsmorethan100mA,alwaysuseasuitablebaseresistor,donotprovidecollector-emittervoltagemorethan40Vandalwaysoperateorstoreintemperaturesabove-55centigradeandbelow+150centigrade.ComponentDatasheet2N3904DatasheetFAQWhatisa2N3904Transistor?The2N3904isacommonNPNbipolarjunctiontransistorusedforgeneral-purposelow-poweramplifyingorswitchingapplications.Itisdesignedforlowcurrentandpower,mediumvoltage,andcanoperateatmoderatelyhighspeeds.HowDoesa2N3904TransistorWork?2N3904isaNPNtransistorhencethecollectorandemitterwillbeleftopen(Reversebiased)whenthebasepinisheldatgroundandwillbeclosed(Forwardbiased)whenasignalisprovidedtobasepin.2N3904hasagainvalueof300;thisvaluedeterminestheamplificationcapacityofthetransistor.WhatisPNPNPN?PNPsensorsproduceapositiveoutputtoyourindustrialcontrolsinput,whileNPNsensorsproduceanegativesignalduringanonstate....NPN,orsinkingoutputsensors,workintheoppositeway,sinkinggroundvoltagetoaninputwhenitson.WhatsisATransistor?Atransistorisasemiconductordeviceusedtoamplifyorswitchelectronicsignalsandelectricalpower.Itiscomposedofsemiconductormaterialusuallywithatleastthreeterminalsforconnectiontoanexternalcircuit.WhatistheGainofaTransistor?Thecurrentgainforthecommon-baseconfigurationisdefinedasthechangeincollectorcurrentdividedbythechangeinemittercurrentwhenthebase-to-collectorvoltageisconstant.Typicalcommon-basecurrentgaininawell-designedbipolartransistorisveryclosetounity.

TPS54331

The74HC595isoneofthemostcommonlyusedshiftregisters.Asapopularcomponent,ithasmanysubstituteswhosespecifications,applications,andpinoutareverymuchalike.Intodaysblog,wellcomparethe74HC595tothoseofitsalternativecomponents:74LS595,74HC164,andMCP23017,toseewhataretheirdifferencesandiftheycanbeusedinterchangeably,andsoon.Catalog74HC595VS74LS59574HC595VS74HC16474HC595vsMCP2301774HC595VS74LS595ComponentDatasheet74HC595Datasheet74LS595Datasheet74HC595BasicsThe74HC595isanhighspeedCMOS8-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.74LS595Basics74LS595containsan8-bitserial-in,parallel-outshiftregisterthatfeedsan8-bitD-typestorageregister.Thestorageregisterhasparallel3-state(LS595)oropen-collector(LS596)outputs.Separateclocksareprovidedforboththeshiftregisterandthestorageregister.Theshiftregisterhasadirect-overridingclear,serialinput,andserialoutputpinsforcascading.Boththeshiftregisterandstorageregisterclocksarepositive-edgetriggered.Iftheuserwishestoconnectbothclockstogether,theshiftregisterstatewillalwaysbeoneclockpulseaheadofthestorageregister.74HC595VS74LS59574LS595isTTLbased,fast,usesmorepoweranditisolder.74HC595isCMOSbased,fast,useslesspowerandisthemostup-to-dateversion.Tobemorespecific,theLSseriesisbuiltwithbipolartransistorsandisbasedonTTL(totaltransistorlogic)(BJT).BJTswereamongthefirsttransistorsusedinintegratedcircuits.TheHCseriesemploysCMOS(complementarymetaloxidesemiconductor)devices,whicharealatergenerationtransistorthat,asthenameimplies,usemetaloveranoxideasthegateinthetransistor(nowpolysiliconoveranoxide).TheadvantageofthesedevicesisthattheirinputimpedanceismuchhigherthanthatofaBJT,resultinginmuchlowercurrentandpowerconsumption.Asageneralrule(withexceptions),CMOSisusedinlogicdeviceswithlowpowerrequirements,andBJTsareusedinhigherpowerdevices(switching,powermanagementapps,etc).TherearealsoBiCMOSdevices,whichcombineCMOSandBJTsonthesamediyandutilizethebestcharacteristicsofeachdevice.74HC595VS74HC164ComponentDatasheet74HC595Datasheet74HC164Datasheet74HC164BasicsThe74HC164isan8-bitserial-in/parallel-outshiftregister.Thedevicefeaturestwoserialdatainputs(DSAandDSB),eightparalleldataoutputs(Q0toQ7).DataisenteredseriallythroughDSAorDSBandeitherinputcanbeusedasanactiveHIGHenablefordataentrythroughtheotherinput.DataisshiftedontheLOW-to-HIGHtransitionsoftheclock(CP)input.ALOWonthemasterresetinput(MR)clearstheregisterandforcesalloutputsLOW,independentlyofotherinputs.Inputsincludeclampdiodes.ThisenablestheuseofcurrentlimitingresistorstointerfaceinputstovoltagesinexcessofVCC.74HC595VS74HC16474HC164isserialinandparallelout,liketheCD4015,but74HC595isfasterandlowervoltage.Thedifferencebetweenthe74HC595andthe74HC164isthatthe74HC164doesnotbufferthedata(internalspaceexistedonthe74HC595),sotheLEDFLASHESasitdragsthebitstothetip-toe,givingtheflashingeffectseeninthe74HC164butnotonthe74HC595.Tobemorespecific:74HC595hasalatch,sotheoutputcanremainunchangedduringtheshift;74HC164hasnolatch,soitchangeseverytimeashiftclockisgenerated.Thisisthebiggestdifferencebetweenthetwo.74HC595usesspecialQ7pintorealizemulti-chipcascade;74HC164directlyusesoutputpinQ7tocascade74HC595hasenableOE,whenOEisinvalid,theoutputpinishighimpedance;while74HC164hasnoenablepinTheresetof74HC595isfortheshiftregister.IfyouwanttoresettheLATCHregister,youmustloadtheshiftregistercontentintothelatchregisterontherisingedgeofST_CP;thatistosay:74HC595resetissynchronous,74HC164resetisasynchronous,Sotheresetof74HC164iseasier74HC164hasacorresponding74HC165parallel-to-serialchip.74HC595vsMCP23017ComponentDatasheet74HC595DatasheetMCP23017DatasheetMCP23017BasicsTheMCP23017isaportexpanderthatgivesyouvirtuallyidenticalPORTScomparedtostandardmicrocontrollerse.g.ArduinoorPICdevicesanditevenincludesinterrupts.Itgivesyouanextra16I/OpinsusinganI2Cinterfaceaswellascomprehensiveinterruptcontrol.74HC595VSMCP23017Tobeshort,74HC595isashiftregister,whileMCP23017isanIOExpander.IfyouwanttodriveLEDsdirectlyyoucouldjustgofor74HC595,butyouwantacomponentthatismoreflexibleintheprojects,MCP23017isagoodchoice,whatsmore,theycanprettymuchusethesamesoftware.AboutshiftregisterandIOExpander,themaindifferencesarespeedcomplexityindrivingthem.Shiftregistersareeasiertodrive,theyaresimpleserialtoparallelconverters.Shiftregisterswillrunasfastasyoucanpumpdatathroughthem.IOexpandersmaybemoreversatilebutarelimitedtothei2cinterfacewhichrelativelyspeakingisdogslow.SPIexpanderswouldbebetterbuteventhentheyarenotasfastasshiftregisters.Thereareprosandconstoeverythingandinmostcasesyoucanuseeitheroneandpeopleusewhattheyaremorefamiliarwith.

DS1307isalow-powerFullBinary(BCD)RealTimeClock(RTC)ICwith56bytesofSVRAMthatcommunicatesviaI2CProtocol.ThisblogprovidesyouadetailedintroductiontoDS1307RTC,includingitspinout,application,howdoesitworkinacircuit,whatsitsdifferencebetweenDS3231andmore,hopethisbloghelpsandthankyouforreading!ThisisatutorialvideoteachingpeoplehowtoconnectDS1307withArduino.CatalogDS1307DescriptionDS1307PinoutDS1307FeaturesDS1307ParameterWhatisI2CProtocolDS1307WorkingPrincipleHowtoUseDS1307DS1307vsDS3231DS1307ApplicationDS1307ManufacturerDS1307PackageComponentDatasheetFAQDS1307DescriptionTheDS1307serialreal-timeclock(RTC)isalow-power,fullbinarycodeddecimal(BCD)clock/calendarplus56bytesofNVSRAM.AddressanddataaretransferredseriallythroughanI2C,bidirectionalbus.Theclock/calendarprovidesseconds,minutes,hours,day,date,month,andyearinformation.Theendofthemonthdateisautomaticallyadjustedformonthswithfewerthan31days,includingcorrectionsforleapyear.Theclockoperatesineitherthe24-houror12-hourformatwithAM/PMindicator.TheDS1307hasabuilt-inpower-sensecircuitthatdetectspowerfailuresandautomaticallyswitchestothebackupsupply.Timekeepingoperationcontinueswhilethepartoperatesfromthebackupsupply.TheDS1307canoperateinthefollowingtwomodes:SlaveReceiverMode(WriteMode):SerialdataandclockarereceivedthroughSDAandSCL.SlaveTransmitterMode(ReadMode):Thefirstbyteisreceivedandhandledasintheslavereceivermode.However,inthismode,thedirectionbitwillindicatethatthetransferdirectionisreversed.DS1307PinoutDS1307RTCDS1307RTCPinoutPinNumberPinNameDescription1,2X1,X2CrystalOscillatorshouldbeconnectedtothesepins3V-BatConnectedtoPositiveterminalofthebattery4GroundGroundpinoftheIC5,6SCLandSDAPinsforI2CcommunicationwithCPU7SQW/OutSquarewaveoutputdriverpintoobtainsquarewavefrequencies.8VccPowerstheICtypically5VDS1307FeaturesI2CInterfaceRTCICOperatingVoltage:5VLessthan500nAcurrentwhenoperatingwithbattery56bytesSVRAMOperatesinpowerorbatterymodeProgrammablesquarewaveoutputpinAvailableinPDIPandSOpackageDS1307ParameterType:Clock/CalendarFeatures:LeapYearNVSRAMSquareWaveOutputBaseProductNumber:DS1307Interface:IC2-WireSerialMemorySize:56BTimeFormat:HHDateFormat:YY-MM-DD-ddVoltage-SupplyBattery:2V~3.5VCurrent-Timekeeping(Max):200A@5VWhatisI2CProtocolI2Cisaserialprotocolthattransfersdatabitbybit.I2CcombinesthebestcharacteristicsofSPIandUART.Wecancontrolmanyslavedevicesbyusingitwithasinglemicrocontroller.DataistransferredintheformofmessagesinI2C,andthemessagesarethenconvertedintodata.Eachmessagecontainsanaddressframecontainingabinaryaddressofthedevicesundercontrol.TheI2CprotocolislessexpensivetoimplementthantheSPIprotocol.SPIcontrolsasingleslavedevice,whereasI2Ccontrolsmultipledevices.LetstakealookattheI2Cprotocoldiagramforabetterunderstanding.DS1307WorkingPrincipleLetslookatacircuitthatusestheDS1307togetabetterunderstandingofhowitworks.Inthissimplecircuit,weconnectthechipsfirsttwopins,X1andX2,toa32.768kHzcrystaloscillatorasthesource.Thethirdpinislinkedtoa3Vbattery.Weprovidea5vsupplyatVcc,whichcanbeprovidedbyamicrocontroller.IfVccisnotsupplied,thereadandwriteconditionsaredisabled.WhenusingtheI2cprotocol,adevicemusthavestartandstopconditionsinordertocommunicatewithotherdevices.Weprovideaspecificidentificationandaddressregistertoadeviceinordertoobtainthestartcondition.Forabetterunderstandingofstopandstartconditionletshavealookatclockfigure.HowtoUseDS1307TheDS1307isan8-pinICthatrunson5VandcommunicateswiththeCPUviatheI2Cprotocol.AtypicalapplicationcircuitfortheDS1307isshownbelow,takenfromtheDS1307datasheet.Asyoucansee,theIChasSCL(SerialClock)andSDA(SerialData)pinsthatitusestocommunicatewiththeCPU;bothofthesepinsmustbepulledhighusingaresistor.TheICcanbepoweredbyapplying5VtotheVccpin;ifthepowerfails,itwillautomaticallyswitchtobatterymode,obtainingpowerfromaLithiumcellconnectedtopinVbatandground.PinsX1andX2areusedtoconnectthecrystaloscillator,whichistypicallya32.7KHzQuartzcrystal.TheSQWpingeneratesaPWMsquarewavewithprogrammablefrequenciesof1Hz,4KHz,8KHz,or32KHz.Thispinalsonecessitatestheuseofapull-upresistor.OnlytheI2CprotocolisusedtoexchangedatabetweentheCPUandtheRTCIC.Thiscommunicationfacilitatesbothreadingandwriting.TheICcanprovideinformationsuchasaReal-TimeClockthatcountsseconds,minutes,hours,thedateofthemonth,themonth,thedayoftheweek,andtheyear,withLeap-YearCompensationValidUpto2100.DS1307vsDS3231DS3231TheDS3231isalsoalow-cost,extremelyaccurateI2Creal-timeclock(RTC).ButitisaRTCwithanintegratedtemperature-compensatedcrystaloscillator(TCXO)andcrystal.Thedeviceincorporatesabatteryinput,andmaintainsaccu-ratetimekeepingwhenmainpowertothedeviceisinter-rupted.ThemaindistinctionbetweentheDS3231andtheDS1370istheaccuracyoftime-keeping.TheDS1307includesanexternal32kHzcrystalfortimekeeping,thefrequencyofwhichiseasilyaffectedbyexternaltemperature.Asaresult,theclockisusuallyoffbyaboutfiveorsominutespermonth.TheDS3231,ontheotherhand,ismuchmoreaccuratebecauseitincludesaninternalTemperatureCompensatedCrystalOscillator(TCXO)thatisunaffectedbytemperature,allowingittobeaccuratetoafewminutesperyearatmost.DS1307isstillagreatvalueRTCthatwillserveyouwell,butDS3231isrecommendedforprojectsthatrequiremoreaccuratetime-keeping.DS1307ApplicationRoboticsGamingServersComputerPeripheralsGPSUtilitypowermetersDS1307ManufacturerMaximIntegrateddevelopsinnovativeanalogandmixed-signalproductsandtechnologiestomakesystemssmallerandsmarter,withenhancedsecurityandincreasedenergyefficiency.Weareempoweringdesigninnovationforourautomotive,industrial,healthcare,mobileconsumer,andclouddatacentercustomerstodeliverindustry-leadingsolutionsthathelpchangetheworld.DS1307PackageComponentDatasheetDS1307RTCDatasheetFAQWhatisDS1307?TheDS1307isalowpowerFullBinary(BCD)RealTimeClock(RTC)ICwith56bytesofSVRAMthatcommunicatesthroughI2CProtocol.TheICcanworkfromdirectlysupplyonVccandswitchtoBatteryautomaticallywhenrequired.HowdoIknowifDS1307isworking?IfyouhadaMasterI2C/SMBusEnginetoolbuiltup,youcouldconnectjustitandtheDS1307together(withpull-upsandotheressentialsofcourse)andquicklyseeifyoucancommunicatewiththeDS1307inafewminutes.Ifyoucan,thenyouknowthatyourDS1307isworkinganditcouldbeyourCcode.HowdoIresetmyRTCDS1307?Sotostart,removethebatteryfromtheholderwhiletheArduinoisnotpoweredorpluggedintoUSB.Wait3secondsandthenreplacethebattery.ThisresetstheRTCchip.WhyRTCisused?Areal-timeclock(RTC)isanelectronicdevice(mostoftenintheformofanintegratedcircuit)thatmeasuresthepassageoftime.Althoughthetermoftenreferstothedevicesinpersonalcomputers,serversandembeddedsystems,RTCsarepresentinalmostanyelectronicdevicewhichneedstokeepaccuratetime.On the other hand it can also be used in audio amplifier stages and as a separate amplifier to drive a 2 to 3 inch speaker directly.

push({});Where We Can Use it How to Use:This transistor can be used in many general purpose applications for example if one is using it as a switch it can drive many loads at a time under -1.(Check pin configuration of any transistor you are using before replacing in your circuit).

It can handle or drive maximum collector current of -1.push({});Features / technical specifications:Package Type: TO-126Transistor Type: PNPMax Collector Current(IC): –5AMax Collector-Emitter Voltage (VCE): –45VMax Collector-Base Voltage (VCB): –45VMax Emitter-Base Voltage (VEBO): –5VMax Collector Dissipation (Pc): 5 WattMax Transition Frequency (fT): 190 MHzMinimum Maximum DC Current Gain (hFE): 25 – 250Max Storage Operating temperature Should Be: -55 to +150 CentigradeNPN Complementary:NPN Complementary of BD136 is BD135Replacement and Equivalent:BD138.

访客,请您发表评论:

Powered By Tkool Electronics

Copyright Your WebSite.sitemap