SNVS590M –SEPTEMBER 2008–REVISED NOVEMBER 2014 …

1 lm22674 -ADJVINENSWBOOTFBGNDVINVOUTP roductFolderSample &BuyTechnicalDocumentsTools &SoftwareSupport &CommunityLM22674, lm22674 -Q1 SNVS590M SEPTEMBER2008 REVISEDNOVEMBER2014LM22674/-Q142 V, 500 mA SIMPLESWITCHER Step-DownVoltageRegulatorwith Features1 Features3 DescriptionThe LM22674switchingregulatorprovidesall of the1 V to 42 Vfunctionsnecessaryto implementan efficienthigh InternallyCompensatedVoltageModeControlv oltagestep-down(buck)regulatorusinga minimum Stablewith Low ESRC eramicCapacitorsof use regulatorincorporatesa 42 V N-channelMOSFET switch 200 m N-ChannelMOSFET capableof providingup to 500 mA of loadcurrent. OutputVoltageOptions:Excellentline andloadregulationalongwithhigh-ADJ(Outpu tsas Low as )efficiency(> 90%)are (OutputFixedto 5 V)offersshortminimumon-time,allowingthe widest the useris free fromthe SwitchingFrequencyof 500 kHztedioustaskof calculatingthe loopcompensation 40 C to 125 C V outputand adjustableoutputRangevoltageoptionsare switchingfrequency PrecisionEnablePinof 500 kHz allowsfor precisionenableinput IntegratedBoot-StrapDiodeallowssimplific ationof regulatorcontroland system shutdownmodethe regulator FullyWEBENCH Enableddrawsonly 25 A (typ).

2 Builtin soft-start(500 s, typ) LM22674alsohas lm22674 -Q1is an AutomotiveGradeProductbuiltin thermalshutdown,andcurrentlimitingtothat is AEC-Q100 Grade1 Qualified( 40 C toprotectagainstaccidentaloverloads.+125 C OperatingJunctionTemperature) SO PowerPAD(ExposedPad)TheLM22674deviceis a memberof TexasInstruments'SIMPLESWITCHER conceptprovidesfor an easy2 Applicationsto use completedesignusinga minimumnumberof IndustrialControlexternalcomponentsand the TI WEBENCH design Telecomand 's WEBENCH tool includesfeaturessuchasexternalcomponentc alculation,electricalsimulation, EmbeddedSystemsthermalsimulation,andBuil d-Itboardsfor easy ConversionsfromStandard24 V, 12 V and 5 (1)PARTNUMBERPACKAGEBODYSIZE(NOM) lm22674 HSOP(8) x (1)

3 For all availablepackages,see the orderableaddendumatthe end of the IMPORTANTNOTICEat the end of this datasheetaddressesavailability,warranty, changes,use in safety-criticalapplications,intellectual propertymattersand , lm22674 -Q1 SNVS590M SEPTEMBER2008 Applicationsand Pin Configurationand Deviceand Mechanical,Packaging,and RevisionHistoryChangesfromRevisionL (April2013)to RevisionMPage AddedPin Configurationand Functionssection,HandlingRatingtable,The rmalInformationtable,FeatureDescriptions ection,DeviceFunctionalModes,Application and Implementationsection,PowerSupplyRecomme ndationssection,Layoutsection,Deviceand DocumentationSupportsection,andMechanica l,Packaging,and 2008 2014,TexasInstrumentsIncorporatedProduct FolderLinks.

4 LM22674LM22674-Q1 Exposed PadConnect to GNDNC3FB4 BOOT 1NC 28 SW7 VIN6 GND5 ENLM22674, SEPTEMBER2008 REVISEDNOVEMBER20145 Pin Configurationand Functions8-PinHSOPP ackageTop ViewPin gatevoltagefor the high side controlregulatorstart-upand UVLO sectionof not electricallyconnectedto die. Pinsdo functionas thermalNC2, 3 Not regulatorSW8 OSwitchpinSwitchingoutputof regulatorCopyright 2008 2014,TexasInstrumentsIncorporatedSubmitD ocumentationFeedback3 ProductFolderLinks:LM22674LM22674-Q1LM22 674, lm22674 -Q1 SNVS590M SEPTEMBER2008 (1)(2)MINMAXUNITVIN to GND43 VEN Pin Voltage to GND(3) 5 VINVBOOTPin VoltageVSW+ 7 VFB Pin Voltage CFor solderingspecifications,referto ApplicationReportAbsoluteMaximumRatingsf or Soldering(SNOA549).

5 (1)AbsoluteMaximumRatingsindicatelimitsb eyondwhichdamageto the devicemay occur,includinginoperabilityand the deviceand/ornon-degradationat the AbsoluteMaximumRatingsorotherconditionsb eyondthoseindicatedin theRecommendedOperatingConditionsis not whichthe deviceis functionaland shouldnot be operatedbeyondsuchconditions.(2)If Military/Aerospacespecifieddevicesare required,pleasecontactthe TexasInstrumentsSalesOffice/Distributors for availabilityandspecifications(3)The absolutemaximumspecificationof the SW to GND appliesto dc extendednegativevoltagelimit of -10 V appliesto apulseof up to 50 : lm22674 MINMAXUNITTstgStoragetemperaturerange 65150 CHumanbodymodel(HBM),per ANSI/ESDA/JEDECJS-001,allV(ESD)Electrost aticdischarge 22kVpins(1)(1)JEDEC documentJEP155statesthat 500-VHBM allowssafe manufacturingwith a.

6 lm22674 -Q1 MINMAXUNITTstgStoragetemperaturerange 65150 CV(ESD)ElectrostaticdischargeHumanbodymo del(HBM),per AECQ100-002(1) 22kV(1)AECQ100-002indicatesHBMstressingi s donein accordancewith the ANSI/ 40125 , lm22674 -Q1 THERMALMETRIC(1)UNITDDA8 PINSR JAJunction-to-ambientthermalresistance60 C/W(1)For moreinformationabouttraditionaland new thermalmetrics,see theIC PackageThermalMetricsapplicationreport(S PRA953).4 SubmitDocumentationFeedbackCopyright 2008 2014,TexasInstrumentsIncorporatedProduct FolderLinks:LM22674LM22674-Q1LM22674, SEPTEMBER2008 mostlikelyparametricnormat TA= TJ= 25 C, and are providedfor :VIN= (1)TYP(2)MAX(1) 8 V to 42 8 V to 42 V, 40 C TJ CLM22674-ADJVIN= V to 42 V to 42 V, 40 C TJ CALLOUTPUTVOLTAGEVERSIONSVFB= 5 5 V, 40 C TJ 125 C6 ISTDBYS tandbyQuiescentCurrentEN Pin = 0 V2540 42 V, EN Pin = 0 V, VSW= 0 AILO utputLeakageCurrentVSW= 1 (ON)SwitchOn-Resistance VIN= V to 42 V, 40 C TJ C500fOOscillatorFrequencykHzVIN= V to 42 V, 40 C TJ 400600125 C200 TOFFMINM inimumOff-timensVIN= V to 42 V, 40 C TJ 100300125 CTONMINM inimumOn-time100nsIBIASF eedbackBiasCurrentVFB= V (ADJV ersionOnly) , 40 C TJ 125 Input= 0 V6 ATSDT hermalShutdownThreshold150 C(1)MIN and MAXlimitsare 100%productiontestedat 25 C.

7 Limitsoverthe operatingtemperaturerangeare guaranteedthroughcorrelationusingStatist icalQualityControl(SQC) usedto calculateTI's AverageOutgoingQualityLevel(AOQL).(2)Typ icalvaluesrepresentmostlikelyparametricn ormsat the conditionsspecifiedand are not 2008 2014,TexasInstrumentsIncorporatedSubmitD ocumentationFeedback5 ProductFolderLinks:LM22674LM22674-Q1LM22 674, lm22674 -Q1 SNVS590M SEPTEMBER2008 12 V, TJ= 25 C (unlessotherwisespecified)Figure2. NormalizedSwitchingFrequencyvs TemperatureFigure1. Efficiencyvs IOUTand VIN, VOUT= VFigure4. NormalizedRDS(ON)vs TemperatureFigure3. CurrentLimitvs TemperatureFigure5. FeedbackBiasCurrentvs TemperatureFigure6.

8 NormalizedEnableThresholdVoltagevsTemper ature6 SubmitDocumentationFeedbackCopyright 2008 2014,TexasInstrumentsIncorporatedProduct FolderLinks:LM22674LM22674-Q1LM22674, SEPTEMBER2008 REVISEDNOVEMBER2014 TypicalCharacteristics(continued)Vin= 12 V, TJ= 25 C (unlessotherwisespecified)Figure8. NormalizedFeedbackVoltagevs TemperatureFigure7. StandbyQuiescentCurrentvs InputVoltageFigure9. NormalizedFeedbackVoltagevs InputVoltageCopyright 2008 2014,TexasInstrumentsIncorporatedSubmitD ocumentationFeedback7 ProductFolderLinks:LM22674LM22674-Q1 LOGICOSC+-TYPE IIICOMP+ REG, EN,UVLOGNDSWBOOTVINENFBVINVOUTE rror , lm22674 -Q1 SNVS590M SEPTEMBER2008 LM22674incorporatesa addition,inputvoltagefeedforwardis usedto stabilizethe loopgainagainstvariationsin loopcompensationto be optimizedfor powerMOSFET,in conjunctionwiththe diode,producea rectangularwaveformat the switchpin, that swingsfromaboutzerovoltsto inductorandoutputcapacitoraveragethis waveformto becomethe adjustingthe dutycycleofthis waveform.

9 The outputvoltagecan be erroramplifiercomparesthe outputvoltagewith theinternalreferenceand adjuststhe duty cycleto regulatethe outputat the internalloop compensationof the -ADJoptionis optimizedfor outputsof 5V and an outputvoltageof 5 V or greateris required,the optioncan be usedwith an minimumoutputvoltageis equalto the referencevoltage,that is, (typ). UVLOThe precisionenableinput(EN)is usedto controlthe precisionfeatureallowssimplesequencingof multiplepowersupplieswitha pin to groundor to avoltageless V (typ)will turn off the currentdrainfromthe inputsupply,in this state,is25 A (typ)at an inputvoltageof 12 V. The EN inputhas an internalpullupof about6 A.

10 Thereforethis pin canbe left floatingor pulledto a V (typ)to turn the regulatoron. The hysteresison this inputis V (typ)abovethe V (typ) enableinput,the voltagemustneverexceedthe 6 V absolutemaximumspecificationfor this 2008 2014,TexasInstrumentsIncorporatedProduct FolderLinks:LM22674LM22674-Q1 ENVinRENBRENTLM22674, SEPTEMBER2008 REVISEDNOVEMBER2014 FeatureDescription(continued)Althoughan internalpullupis providedon the EN pin, it is goodpracticeto pull the inputhigh,whenthis featureis not used,especiallyin mosteasilybe doneby connectinga resistorbetweenVIN and the EN pin. The resistoris required,becausethe internalzenerdiode,at the EN pin, will conductforvoltagesaboveabout6 V.