LMV7235资料

LMV7235/LMV723945nsec,UltraLowPower,LowVoltage,Rail-to-RailInputComparatorwithOpen-Drain/Push-PullOutputFebruary2002

LMV7235/LMV7239

45ns,UltraLowPower,LowVoltage,Rail-to-RailInputComparatorwithOpen-Drain/Push-PullOutput

GeneralDescription

TheLMV7235/39areultralowpower,lowvoltage,45nscomparators.Theyareguaranteedtooperateoverthefullsupplyvoltagerangeof2.7Vto5V.Thesedevicesachievea45nspropagationdelaywhileconsumingonly65µAofsup-plycurrentat5V.

TheLMV7235/39haveagreaterthanrail-to-railcommonmodevoltagerange.Theinputcommonmodevoltagerangeextends200mVbelowgroundand200mVabovesupply,allowingbothgroundandsupplysensing.

TheLMV7235featuresanopendrainoutput.Byconnectinganexternalresistor,theoutputofthecomparatorcanbeusedasalevelshifter.

TheLMV7239featuresapush-pulloutputstage.Thisfeatureallowsoperationwithouttheneedofanexternalpull-upresistor.

TheLMV7235/39areavailableintheSC70-5andSOT23-5packages,whichareidealforsystemswheresmallsizeandlowpoweriscritical.

Features

(VS=5V,TA=25˚C,Typicalvaluesunlessotherwisespeci-fied)

nPropagationdelay45nsnLowsupplycurrent65µAnRail-to-Railinput

nOpendrainandpush-pulloutput

nIdealfor2.7Vand5Vsinglesupplyapplications

nAvailableinspacesavingpackages:5-pinSOT23-5and5-pinSC70-5

Applications

nnnnnnn

PortableandbatterypoweredsystemsScanners

Settopboxes

HighspeeddifferentiallinereceiverWindowcomparatorsZero-crossingdetectors

Highspeedsamplingcircuits

TypicalApplication

10135902

©2002NationalSemiconductorCorporationDS101359www.national.com

元器件交易网www.cecb2b.com

LMV7235/LMV7239ConnectionDiagram

SC70-5/SOT23-5

10135903

TopView

OrderingInformation

Package

5-pinSC70-5

PartNumberLMV7235M7LMV7235M7XLMV7239M7LMV7239M7XLMV7235M5

5-pinSOT23-5

LMV7235M5XLMV7239M5LMV7239M5X

MarkingC21C21C20C20C21AC21AC20AC20A

Suppliedas1kUnitsTapeandReel3kUnitsTapeandReel1kUnitsTapeandReel3kUnitsTapeandReel1kUnitsTapeandReel3kUnitsTapeandReel1kUnitsTapeandReel3kUnitsTapeandReel

MF05AMAA05ANSCDrawing

SimplifiedSchematic

10135901

www.national.com2

元器件交易网www.cecb2b.com

LMV7235/LMV7239AbsoluteMaximumRatings

(Note1)VoltageatInput/OutputPinsCurrentatInputPin(Note9)

IfMilitary/Aerospacespecifieddevicesarerequired,pleasecontacttheNationalSemiconductorSalesOffice/Distributorsforavailabilityandspecifications.ESDTolerance(Note2)

MachineBodyHumanModelBodyDifferentialInputVoltageOutputShortCircuitDurationSupplyVoltage(V+-V−)SolderingInformation

InfraredorConvection(20sec)WaveSoldering(10sec)

235˚C

260˚C(leadtemp)

100V1000V

(V+)+0.3V(V−)−0.3V

±10mA

OperatingRatings

SupplyVoltages(V+-V−)JunctionTemperatureRange(Note4)

StorageTemperatureRangePackageThermalResistance

SC70-5SOT23-5

478˚C/W265˚C/W2.7Vto5V−40˚Cto+85˚C−65˚Cto+150˚C

±SupplyVoltage

(Note3)

5.5V

2.7VElectricalCharacteristics

Unlessotherwisespecified,alllimitsguaranteedforTJ=25˚C,VCM=V+/2,V+=2.7V,V−=0V−.Boldfacelimitsapplyatthetemperatureextremes.SymbolVOSIBIOSCMRRPSRRVCMParameter

InputOffsetVoltageInputBiasCurrentInputOffsetCurrent

CommonModeRejectionRatioPowerSupplyRejectionRatioInputCommon-ModeVoltageRange

0V50dB

Conditions

Typ(Note5)0.83056285V++0.2−0.2

VOOutputSwingHigh(LMV7239only)

IL=4mA,VID=500mVIL=0.4mA,VID=500mV

OutputSwingLow(LMV7239/LMV7235)

IL=−4mA,VID=−500mVIL=−0.4mA,VID=−500mV

ISCOutputShortCircuitCurrent

Sourcing,VO=0V(LMV7239only)(Note3)

Sinking,VO=2.7V

(LMV7235RL=10k)(Note3)

ISSupplyCurrent

Noload

V+−0.26V+−0.022301515

350450Limits(Note6)

684006002004005265V++0.1V+−0.10V+−0.35

UnitsmVmaxnAmaxnAmaxdBmindBminVminVmaxVminVminmVmaxmVmaxmA

2052

85100

mAµAmax

3www.national.com

元器件交易网www.cecb2b.com

LMV7235/LMV72392.7VElectricalCharacteristics

SymboltPDParameter

PropagationDelay

(Continued)

Unlessotherwisespecified,alllimitsguaranteedforTJ=25˚C,VCM=V+/2,V+=2.7V,V−=0V−.Boldfacelimitsapplyatthetemperatureextremes.

Conditions

Overdrive=20mV(Note10)

Overdrive=50mV(Note10)

Overdrive=100mV(Note10)

Typ(Note5)68635051.7112

Limits(Note6)

Unitsnsnsnsnsnsns

tSKEWtrPropagationDelaySkew(LMV7239only)OutputRiseTime

(Note8)LMV723910%to90%LMV723510%to90%(Note10)

tfILEAKAGEOutputFallTimeOutputLeakageCurrent(LMV7235only)

90%to10%1.73

nsnA

5VElectricalCharacteristics

Unlessotherwisespecified,alllimitsguaranteedforTJ=25˚C,VCM=V+/2,V+=5V,V−=0V.Boldfacelimitsapplyatthetemperatureextremes.SymbolVOSIBIOSCMRRPSRRVCMParameter

InputOffsetVoltageInputBiasCurrentInputOffsetCurrent

CommonModeRejectionRatioPowerSupplyRejectionRatioInputCommon-ModeVoltageRange

0V50dB

Conditions

Typ(Note5)

13056785V++0.2−0.2

VOOutputSwingHigh(LMV7239only)

IL=4mA,VID=500mVIL=0.4mA,VID=500mV

OutputSwingLow(LMV7239/LMV7235)

IL=−4mA,VID=−500mVIL=−0.4mA,VID=−500mV

V+−0.15V+−0.0123010

350450Limits(Note6)

684006002004005265V++0.1V+−0.10V+−0.25

UnitsmVmaxnAmaxnAmaxdBmindBminVminVmaxVminVminmVmaxmVmax

www.national.com4

元器件交易网www.cecb2b.com

LMV7235/LMV72395VElectricalCharacteristics

SymbolISCParameter

OutputShortCircuitCurrent

(Continued)

Unlessotherwisespecified,alllimitsguaranteedforTJ=25˚C,VCM=V+/2,V+=5V,V−=0V.Boldfacelimitsapplyatthetemperatureextremes.

Conditions

Sourcing,VO=0V(LMV7239only)(Note3)

Sinking,VO=5V(LMV7235RL=10k)(Note3)

Typ(Note5)55

Limits(Note6)2515302095110

UnitsmAminmAminµAmaxnsmaxnsmaxnsmaxnsnsns

60

IStPDSupplyCurrentPropagationDelay

Noload

Overdrive=20mV(Note10)

Overdrive=50mV(Note10)

Overdrive=100mV(Note10)

6562574551.2100

tSKEWtrPropagationDelaySkew(LMV7239only)OutputRiseTime

(Note8)LMV723910%to90%LMV723510%to90%(Note10)

tfILEAKAGEOutputFallTimeOutputLeakeageCurrent(LMV7235only)

90%to10%1.23

nsnA

Note1:AbsoluteMaximumRatingsindicatelimitsbeyondwhichdamagetothedevicemayoccur.OperatingRatingsindicateconditionsforwhichthedeviceisintendedtobefunctional,butspecificperformanceisnotguaranteed.Forguaranteedspecificationsandthetestconditions,seetheElectricalcharacteristics.Note2:Humanbodymodel,1.5kΩinserieswith100pF.Machinemodel,200pF.

Note3:Appliestobothsingle-supplyandsplit-supplyoperation.Continuousshortcircuitoperationatelevatedambienttemperaturecanresultinexceedingthemaximumallowedjunctiontemperatureof150˚C.Outputcurrentsinexcessof±30mAoverlongtermmayadverselyaffectreliability.

Note4:ThemaximumpowerdissipationisafunctionofTJ(max),θJA,andTA.ThemaximumallowablepowerdissipationatanyambienttemperatureisPD=(TJ(max)-TA)/θJA.AllnumbersapplyforpackagessoldereddirectlyintoaPCboard.Note5:TypicalValuesrepresentthemostlikelyparametricnorm.Note6:Alllimitsareguaranteedbytestingorstatisticalanalysis.

Note7:CMRRisnotlinearoverthecommonmoderange.Limitsareguaranteedovertheworstcasefrom0toVCC/2orVCC/2toVCC.Note8:PropagationDelaySkewisdefinedastheabsolutevalueofthedifferencebetweentPDLHandtPDHL.

Note9:Limitinginputpincurrentisonlynecessaryforinputvoltagesthatexceedabsolutemaximuminputvoltageratings.

Note10:A10kpull-upresistorwasusedwhenmeasuringtheLMV7235.TherisetimeoftheLMV7235isafunctionoftheR-Ctimeconstant.

5www.national.com

元器件交易网www.cecb2b.com

LMV7235/LMV7239TypicalPerformanceCharacteristics

SupplyCurrentvs.SupplyVoltage

(Unlessotherwisespecified,VS=5V,CL=10pF,TA=25˚C).

SourcingCurrentvs.OutputVoltage

10135904

10135905

SourcingCurrentvs.OutputVoltageSinkingCurrentvs.OutputVoltage

10135906

10135907

SinkingCurrentvs.OutputVoltageInputBiasCurrentvs.InputVoltage

10135909

10135908

www.national.com6

元器件交易网www.cecb2b.com

LMV7235/LMV7239TypicalPerformanceCharacteristics

25˚C).(Continued)

InputBiasCurrentvs.InputVoltage

(Unlessotherwisespecified,VS=5V,CL=10pF,TA=

PropagationDelayvs.Temperature

10135910

10135911

PropagationDelayvs.CapacitiveLoadPropagationDelayvs.CapacitiveLoad

1013591210135913

PropagationDelayvs.InputOverdrivePropagationDelayvs.InputOverdrive

1013591410135915

7www.national.com

元器件交易网www.cecb2b.com

LMV7235/LMV7239TypicalPerformanceCharacteristics

25˚C).(Continued)

PropagationDelayvs.CommonModeVoltage

(Unlessotherwisespecified,VS=5V,CL=10pF,TA=

PropagationDelayvs.CommonModeVoltage

1013591610135917

ApplicationSection

TheLMV7235/LMV7239aresinglesupplycomparatorswith45nsofpropagationdelayandonly65µAofsupplycurrent.TheLMV7235/LMV7239arerail-to-railinputandoutput.Thetypicalinputcommonmodevoltagerangeof−0.2Vbelowthegroundto0.2Vabovethesupply.TheLMV7235/39useacomplimentaryPNPandNPNinputstageinwhichthePNPstagesensescommonmodevoltagenearV−andtheNPNstagesensescommonmodevoltagenearV+.Ifeitheroftheinputsignalsfallsbelowthenegativecommonmodelimit,theparasiticPNjunctionformedbythesubstrateandthebaseofthePNPwillturnonresultinginanincreaseofinputbiascurrent.

Ifoneoftheinputgoesabovethepositivecommonmodelimit,theoutputwillstillmaintainthecorrectlogiclevelaslongastheotherinputstayswithinthecommonmoderange.However,thepropagationdelaywillincrease.Whenbothinputsareoutsidethecommonmodevoltagerange,currentsaturationoccursintheinputstage,andtheoutputbecomesunpredictable.

Thepropagationdelaydoesnotincreasesignificantlywithlargedifferentialinputvoltages.However,largedifferentialvoltagesgreaterthanthesupplyvoltageshouldbeavoidedtopreventdamagetotheinputstage.

TheLMV7239hasapush-pulloutput.Whentheoutputswitches,thereisadirectpathbetweenVCCandground,causinghighoutputsinkingorsourcingcurrentduringthetransition.Afterthetransition,theoutputcurrentdecreasesandthesupplycurrentsettlesbacktoabout65µAat5V,thusconservingpowerconsumption.

TheLMV7235hasanopendrainthatrequiresapull-upresistortoapositivesupplyvoltagefortheoutputtoswitchproperly.Whentheinternaloutputtransistorisoff,theoutputvoltagewillbepulleduptotheexternalpositivevoltage.

ComparatorwithHysteresis

Thebasiccomparatorconfigurationmayoscillateorproduceanoisyoutputiftheapplieddifferentialinputvoltageisnearthecomparator’soffsetvoltage.Thisusuallyhappenswhentheinputsignalismovingveryslowlyacrossthecompara-tor’sswitchingthreshold.Thisproblemcanbepreventedbytheadditionofhysteresisorpositivefeedback.InvertingComparatorwithHysteresis

TheinvertingcomparatorwithhysteresisrequiresathreeresistornetworkthatisreferencedtothesupplyvoltageVCCofthecomparator.WhenVINattheinvertinginputislessthanVA,thevoltageatthenon-invertingnodeofthecom-parator(VINVA1=VCCR2/((R1//R3)+R2)WhenVINisgreaterthanVA(VIN>VA),theoutputvoltageislow,veryclosetoground.InthiscasethethreenetworkresistorscanbepresentedasR2//R3inserieswithR1.TheuppertripvoltageVA2isdefinedas

VA2=VCC(R2//R3)/((R1+(R2//R3)Thetotalhysteresisprovidedbythenetworkisdefinedas

DeltaVA=VA1-VA2ToassurethatthecomparatorwillalwaysswitchfullytoVCCandnotbepulleddownbytheloadtheresistors,valuesshouldbechosenasfollow:

RPULL-UP<元器件交易网www.cecb2b.com

LMV7235/LMV7239ApplicationSection

(Continued)

10135924

10135919

FIGURE1.

10135920

Non-InvertingComparatorwithHysteresis

Anoninvertingcomparatorwithhysteresisrequiresatworesistornetwork,andavoltagereference(VREF)atthein-vertinginput.WhenVINislow,theoutputisalsolow.Fortheoutputtoswitchfromlowtohigh,VINmustriseuptoVIN1whereVIN1iscalculatedby.

VIN1=R1*(VREF/R2)+VREFWhenVINishigh,theoutputisalsohigh,tomakethecomparatorswitchbacktoit’slowstate,VINmustequalVREFbeforeVAwillagainequalVREF.VINcanbecalculatedby

VIN2=(VREF(R1+R2)-VCCR1)/R2ThehysteresisofthiscircuitisthedifferencebetweenVIN1andVIN2.

DeltaVIN=VCCR1/R2

FIGURE2.Non-InvertingComparatorwithHysteresisCircuitLayoutandBypassing

TheLMV7235/39requirehighspeedlayout.Followtheselayoutguidelines:

1.Useprintedcircuitboardwithagood,unbrokenlow-inductancegroundplane.

2.Placeadecouplingcapacitor(0.1µFceramicsurfacemountcapacitor)ascloseaspossibletoVCCpin.

3.Ontheinputsandtheoutput,keepleadlengthsasshortaspossibletoavoidunwantedparasiticfeedbackaroundthecomparator.Keepinputsawayfromoutput.

4.Solderthedevicedirectlytotheprintedcircuitboardratherthanusingasocket.

5.Forslowmovinginputsignals,takecaretopreventpara-siticfeedback.Asmallcapacitor(1000pForless)placedbetweentheinputscanhelpeliminateoscillationsinthetransitionregion.ThiscapacitorcausessomedegradationtotPDwhenthesourceimpedanceislow.

6.Thetopsidegroundplanerunsbetweentheoutputandinputs.

7.Groundtracefromthegroundpinrunsunderthedeviceuptothebypasscapacitor,shieldingtheinputsfromtheoutputs.

9www.national.com

元器件交易网www.cecb2b.com

LMV7235/LMV7239ApplicationSection

Zero-CrossingDetector

(Continued)

Theinvertinginputisconnectedtogroundandthenon-invertinginputisconnectedto100mVp-psignal.Asthesignalatthenon-invertinginputcrosses0V,thecompara-tor’soutputchangesstate.

theinvertinginputnodeatanappropriateDCaveragelevelbasedontheoutput.Thecrystal’spathprovidesresonantpositivefeedbackandstableoscillationoccurs.Theoutputdutycycleforthiscircuitisroughly50%,butitisaffectedbyresistortolerancesandtoalesserextentbythecomparatoroffset.

10135918

10135922

FIGURE3.Zero-CrossingDetector

FIGURE5.CrystalOscillator

ThresholdDetector

Insteadoftyingtheinvertinginputto0V,theinvertinginputcanbetiedtoareferencevoltage.Thenon-invertinginputisconnectedtotheinput.AstheinputpassestheVREFthresh-old,thecomparator’soutputchangesstate.

IRReceiver

TheLMV7239isanidealcandidatetobeusedasaninfraredreceiver.Theinfraredphotodiodecreatesacurrentrelativetotheamountofinfraredlightpresent.ThecurrentcreatesavoltageacrossRD.Whenthisvoltagelevelcrossthevoltageappliedbythevoltagedividertotheinvertinginput,theoutputtransitions.

10135921

FIGURE4.ThresholdDetector

CrystalOscillator

AsimplecrystaloscillatorusingtheLMV7239isshownbelow.ResistorsR1andR2setthebiaspointatthecom-parator’snon-invertinginput.ResistorsR3,R4andC1sets

FIGURE6.IRReceiver

10135923

www.national.com10

元器件交易网www.cecb2b.com

LMV7235/LMV7239PhysicalDimensions

inches(millimeters)unlessotherwisenoted

5-PinSC70-5

NSPackageNumberMAA05A

11www.national.com

元器件交易网www.cecb2b.com

LMV7235/LMV723945nsec,UltraLowPower,LowVoltage,Rail-to-RailInputComparatorwithOpen-Drain/Push-PullOutputPhysicalDimensions

inches(millimeters)unlessotherwisenoted(Continued)

5-PinSOT23-5

NSPackageNumberMF05A

LIFESUPPORTPOLICY

NATIONAL’SPRODUCTSARENOTAUTHORIZEDFORUSEASCRITICALCOMPONENTSINLIFESUPPORTDEVICESORSYSTEMSWITHOUTTHEEXPRESSWRITTENAPPROVALOFTHEPRESIDENTANDGENERALCOUNSELOFNATIONALSEMICONDUCTORCORPORATION.Asusedherein:1.Lifesupportdevicesorsystemsaredevicesorsystemswhich,(a)areintendedforsurgicalimplantintothebody,or(b)supportorsustainlife,andwhosefailuretoperformwhenproperlyusedinaccordancewithinstructionsforuseprovidedinthelabeling,canbereasonablyexpectedtoresultinasignificantinjurytotheuser.

NationalSemiconductorCorporationAmericas

Email:support@nsc.com

NationalSemiconductorEurope

Fax:+49(0)180-5308586Email:europe.support@nsc.com

DeutschTel:+49(0)6995086208EnglishTel:+44(0)8702402171FrançaisTel:+33(0)141918790

2.Acriticalcomponentisanycomponentofalifesupportdeviceorsystemwhosefailuretoperformcanbereasonablyexpectedtocausethefailureofthelifesupportdeviceorsystem,ortoaffectitssafetyoreffectiveness.

NationalSemiconductorAsiaPacificCustomerResponseGroupTel:65-2544466Fax:65-2504466

Email:ap.support@nsc.com

NationalSemiconductorJapanLtd.

Tel:81-3-5639-7560Fax:81-3-5639-7507

www.national.com

Nationaldoesnotassumeanyresponsibilityforuseofanycircuitrydescribed,nocircuitpatentlicensesareimpliedandNationalreservestherightatanytimewithoutnoticetochangesaidcircuitryandspecifications.