D Flip Flop: Circuit, Truth Table, Working, Differences, Diagrams

The given circuit represents the D flip-flop circuit diagram, where the whole circuit is designed with the help of the NAND gate. Here the output of one NAND ... SkiptocontentDFlipFlopIntroduction|DFlipFlopTheoryAflipflopisthefundamentalsequentialcircuitelement,whichhastwostablestatesandcanstoreonebitatatime.Itcanbedesignedusingacombinationalcircuitwithfeedbackandaclock.DFlip-FlopisoneofthatFlipFlopthatcanstoredata.Itcanbeusedtostoredatastaticallyordynamicallydependsonthedesignofthecircuit.DFlip-Flopisusedinmanysequentialcircuitsasregister,counter,etc.WhatisDflipflop?Dflip-floporDataflipflopisatypeofflipFlopthathasonlyonedatainputthatis‘D’andoneclockpulseinputwithtwooutputsQandQbar.ThisFlipFlopisalsocalledadelayflipflopbecausewhentheinputdataisprovidedintothedflip-flop,theoutputfollowstheinputdatadelaybyoneclockpulse.FullFormofDflipflopDstandsforDelayorDatainDflip-Flop.DflipflopDiagramThegivencircuitrepresentstheDflip-flopcircuitdiagram,wherethewholecircuitisdesignedwiththehelpoftheNANDgate.HeretheoutputofoneNANDgateisfeedasoneinputtotheotherNANDgate,whichformsalatch.Then,thelatchisgatedwithtwomoreNANDgateswhereDisoneinputandclockistheotherinput. Fig.CircuitdiagramoftheDflip-flopdesignedwithNANDgateThefinaloutputoftheDflip-flopisQandQbar,whereQbarisalwayscomplementarytoQ.DFlipFlopTruthTableWhatisDFlipFlopTruthTable?Thetruthtableofthedflipflopshowseverypossibleoutputofthedflip-flopwiththeallpossiblecombinationoftheinputtothedflipflop,whereClockandDistheinputtotheDflip-flopandQandQbaristheoutputoftheDflip-flop.CLOCKDQQbar00NOCHANGENOCHANGE01NOCHANGENOCHANGE10011110DflipflopExcitationTableTheexaltationtableorstatetableshowstheminimuminputwithrespecttotheoutputthatcandefinethecircuit.Whichmainlyrepresentsasequentialcircuitwithitspresentandnextstateofoutputwiththepresetinputandclockpulse.ThistableisalsoknownasacharacteristictableforDflip-flop.DinCLKPresentstate‘Q’Nextstate‘Q’X000X0110100011011011111DflipflopBooleanExpressionThebooleanexpressionoftheDflip-flopis Q(t+1)=D becausethenextvalueofQisonlydependentonthevalueofD,whereasthereisadelayofoneclockpulsefrominputDtooutputQ.Fig.K-mapofinput(D)andoutput(Q)oftheDflip-flopHowDFlipFlopWorks?WorkingofDflipflopDFlipflopisabi-stablememoryelement,whichcanstoreonebitatatime,either‘1’or‘0’.WhentheDinputisprovidedtotheFlipFlop,thecircuitcheckfortheclocksignalisthesignaloftheclockishigh(forleveltriggereddflip-flop)thenwitheveryclockpulse,theinputDpropagatestotheoutputQ. Foredgetriggeredflip-flop,thecircuitcheckforthetransitionofclockpulseaccordingtowhichtheflipFloppropagatestheinputtotheoutput;edgetriggeredcanbepositiveedgetriggeredornegativetriggered.PositiveedgetriggeredDflip-flopchangesitsoutputaccordingtoinputwitheverytransitionoftheclockpulsefrom0to1.AsforthenegativeedgetriggeredDflip-flopchangesitsoutputaccordingtoinputwitheverytransitionoftheclockpulsefrom1to0.DflipflopTimingDiagramAsshowninthegivenfigure,thereisaclockpulserepresentation,withwhichD,whichistheinputtoDflip-flop,andQwhichistheoutput,isrepresented,whereQbaristhecomplementoutputoftheoutputQ,hereweseethetimingdiagramofapositiveedgeflipflop,that’swhyheretheoutputchangeswitheverypositivetransitionintheclockpulseaccordingtotheinput.Fig.TimingorWaveformdiagramoftheDflip-flop(positiveedgetriggered).DflipflopBlockDiagramThediagramshownbelowistheblockrepresentationofthedflip-flop,whereDistheinput,theclockisanotherinputtotheFlipFlop,whereapresetandclearsignalisusedtosetorresettheoutputQoftheDflip-flop. WhatisDflipflopSymbol?Fig.BlockrepresentationoftheDflip-flopwithpresetandclearDflipflopClearandPresetThegivenfigureistheblockdiagramofaDflip-flophavingpreset/setandrest/clearasadditionalinputtotheFlipFlop,wherePreset/SetisusedtosettheoutputQoftheflipFlopsetto1.Rest/ClearistosettheoutputQoftheflipFlopto0.Fig.BlockdiagramoftheDflip-flopwithpreset/setandreset/clearDflipflopwithSetDflip-flopcanhavesettheinputasarequirement,anditcanchangetheoutputandsettheoutputQto1.Itcanbesynchronousorasynchronous,Synchronouswhentheoutputcanchangeonlywiththeclockpulse,asynchronousiswhentheoutputcanbesetto1atanypointoftimeregardlessoftheclockpulse.DflipflopwithResetDflip-flopcansometimesreset/clearinputonlyinadditiontodatainputandclockinput,resettingtheoutputQtozeroofthedflipflopasarequirement.Reset/ClearbeactivelowinputoractivehighinputdependsontheFlipFlopdesign.AsynchronousSetandResetDflipflopwithAsynchronousSetandResetDflip-flopcanhaveanasynchronousset/presetandreset/clearasinputindependentoftheclock.ThatmeanstheoutputoftheFlipFlopcanbesetto1withpresetorresetto0withtheresetdespitetheclockpulse,whichmeanstheoutputcanchangewithorwithoutaclock,whichcanresultinasynchronousoutput.DflipflopwithAsynchronousResetDflip-flopscanhaveasynchronousreset,whichcanbeindependentoftheclock.Regardlessoftheclock,theresetcanchangetheoutputQtozero,whichcancauseasynchronousoutput.DflipflopwithSynchronousResetDflip-flopwithsynchronousresetmeanstheoutputcanresettozerowiththeresetinputbutonlywiththeclock,whichmakestheresetinputdependentontheclockpulse;withoutclockpulseresetwillnotbeabletosettheoutputQtozero,whichwillgiveyouasynchronousoutputalways.DFlipFlopwithEnableOtherthanset/presetorreset/clearDflip-flopcanhaveenabledasoneinputwhenenableishigh,theFlipFlopcanoperatewiththedatainputandclockinput,butwhentheenableislowthenregardlessofanyotherinput,theflipFlopstaysinaholdstate.Fig.BlockrepresentationofaDflip-flopwithEnableDflipflopwithEnableTruthTableEnableDQn01NOCHANGE00NOCHANGE111100Table:Dflip-floptruthtablewithenableinput DflipflopTruthTablewithPresetandClearPR(ACTIVELOW)CLR(ACTIVELOW)CLKDQQbar01XX1010XX0100XXNOTDEFINEDNOTDEFINED111110111001111XNOCHANGENOCHNAGETable:Dflip-floptablewithpreset,clearandclockDflipflopTruthTablewithClockandResetCLKRESETDQ0XXNOCHANGE11X010111000Table:Dflip-flopTruthtableresetandclockinputAsynchronousDflipflopWhenDflip-flopgeneratesoutputindependentoftheclocksignal,thentheoutputproducedmaybeasynchronous.Itismainlycausedbyanasynchronousset/presetorclear/resetsignal,whichcansetorresettheoutputoftheflipFlopatanyintentoftime,whichdisruptsynchronicityintheDflip-flop.StateDiagramforDFlipFlopThestatediagramistherepresentationofadifferentstablestatewiththetransitionbetweenthestateswiththecauseoftransition.HereeverystablestateoutputoftheDflip-flopisrepresentedwithacircle.Incontrast,thetransitionbetweenthestateisrepresentedbythearrowbetweenthecircle,whichisleveledwiththecauseofthetransition.Fig.StatediagramoftheDflip-flopWhenthestatechangesfrom0to1,itiscausedbytheinputD,whichishigh,andwhentheoutputstateis0,andatthetimeD=0thatproducesnochangeintheoutput,thearrowwithD=0startswithstate0andalsoreturnstostate0.ASMChartforDflipflopAnalgorithmicstatemachinechartcontainsthreeblocks:stateblock,conditionblock,andconditionaloutputbox.Therectangleboxrepresentsonestate;thediamondboxistheconditionboxtrueorfalseiftheconditiondecidesthebranchtofollow.Fig.ASM(algorithmicstatemachine)chartrepresentationoftheDflip-flopDflipflopschematic|DFlipFlopSchematicCircuit|DTypeFlipFlopSchematicThefigureshowstheschematicrepresentationoftheDflip-flop;theschematicdiagramrepresentstheprocedureusingabstract. TwodiagramsshowtheworkingoftheDflip-flopwhentheclockishighandanothershowingwhentheclockislow.Whentheclockishigh,theinputdatapassesthroughthecircuit,butwhentheclockislow,theinputcannotpassthroughthecircuit,whichshowsregardlessofthechangeininput,therewillbenochangeinoutputwhentheclockislow.Fig.Schematicdiagramrepresentationofthedflip-flop.onefigurewithclockpulselowandotherwithclockpulsehighDynamicDflipflopFlipFlopisgenerallyastaticstoringdevice,butadynamicflipflopcandynamicallystoredata.Inthegivenschematicdiagramofadynamicflipflop,wecanseeacapacitorconnectedtoeachstage.Whenthereisnoclockpulseforalongtime,thecapacitor’schargecanbelost.However,becauseofthepresenceofthecapacitor,thecircuitwillbeabletostoredatadynamically.Fig.ASchematicdiagramoftheDynamicDflip-flopDynamicDflip-flopisdesignedforfasteroperation;theareacoveredbydynamicflipflopislessthanthatofastaticflipflop.DflipflopMetastabilityMetastabilityreferstothestatewhereoutputisnotdeterministic.Itcancauseoscillation,uncleartransitionsinthecircuitry.Forexample,flipFlopfacestheproblemofmetastability;ithappenstoaflipflopwhentheclockpulseanddatachangeatthesameinstateoftime,whichcausestheresulttobehaveunpredictably.ToavoidmetastabilityinflipFloptheoperationofflipFlopshouldoperateconsideringthesetuptimeandholdtimeoftheFlipFlop.Still,metastabilitycannotbeeliminatedcompletely,butitcanbeminimized.ApplicationofDflipflopImportantapplicationsofDflipfloplistedasfollows:Dflip-flopcanbeusedtoproduceacontrolleddelayinthecircuitry.Usedtodesignfrequencydividercircuity.Forcreatingcounters.Fordevelopingregisters.Usedinpipelining.Forsynchronization.Canbeusedtoavoidglitches.Usedtofixclockfrequencyasfortherequirementofthecircuitry.Canbeusedforisolation.AsToggleswitch.CanbeusedforDatatransmission.Sequencegenerator.Canbeusedasamemoryelement.DifferenceBetweenDandTflipflopDFLIP-FLOPTFLIPFLOPTheoutputofadflipflopfollowstheinputwithadelayofoneclockpulse.TheoutputofTflipfloptoggleswithahighinputwitheveryclockpulse.ItisknownasdelayflipflopItisknownastoggleflipflopWithlowinputtheoutputalsochangestolowwithclockpulseWithlowinputtheoutputdoesnotchangeatall,itstaysinholdstate.DifferenceBetweenDflipflopandJKflipflopDflip-flopJKflipflopTheoutputofadflipflopfollowstheinputwithadelayofoneclockpulse.TheoutputofaJKflipflopsetsto1withJandresetsto0withR whenthereisclockpulse.Itisknownasdelayflipflop.Itisalsocalleduniversalflipflop.Ithaslessnumberofinputcombinations.Ithasmorenumberofinputcombinations.DifferenceBetweenDlatchandDflipflopDlatchDflip-flopDlatchisagatedSRlatch,whichdonothaveclockinput Dflip-flopiscombinationofDlatchwithclockinputLesscomplexcircuitComplexcircuitDlatchishasenablesignalwhichcanenableordisablethelatchoperationDflip-flophasclocksignalwhichcanholdoroperatedtheflipflopwhennosetorresetinputisavailable.Dlatchcanbeactivehighinputoractivelowinputlatch.Dflip-flopinwhichdatainputisalwaysactivehigh,wheresetorresetinputcanbeactivehighoractivelowinput.Dlatchisalwaysaleveltriggeredcircuit.Dflip-flopcanbeleveltriggeredoredgetriggeredcircuit.Lessnumberoftransistorisrequiredfordesign.Morenumberoftransistorisrequiredfordesign.Asynchronousinnature.Generallysynchronousinnature.DoesVoltageDropAcrossAResistor:Why,HowAndDetailedInsightsHowtoFindVoltageAcrossResistor:SeveralApproachesAndProblemsExamplePowerVsVoltage:ComparativeAnalysisandFactsWhatIsImpedanceVoltage:Facts,Problems,ExamplesLCPiFilter:PiFilter,Working,CriticalFACTSWhatIsVoltageDropInParallelCircuit:HowtoFind,ExampleProblemsandDetailedFactsPostnavigation←PreviousPostNextPost→LeaveaCommentCancelReplyYouremailaddresswillnotbepublished.Requiredfieldsaremarked*Typehere..Name*Email*WebsiteSavemyname,email,andwebsiteinthisbrowserforthenexttimeIcomment. 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