Actual Size(3 mm x 3 mm)
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TPS71202,TPS71219TPS71229,TPS71247TPS71256,TPS71257
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Dual250mAOutput,UltraLowNoise,HighPSRR,
Low-DropoutLinearRegulator
FEATURES
•••••••••••
Dual250mAHigh-PerformanceRFLDOsAvailableinFixedandAdjustableVoltageOptions(1.2Vto5.5V)HighPSRR:65dBat10kHzUltraLowNoise:32µVrmsFastStart-UpTime:60µs
Stablewith2.2µFCeramicCapacitorExcellentLoad/LineTransientResponse
VeryLowDropoutVoltage:125mVat250mAIndependentEnablePins
ThermalShutdownandIndependentCurrentLimit
AvailableinThermally-EnhancedSONPackage:3mmx3mmx1mm
DESCRIPTION
TheTPS712xxfamilyoflow-dropout(LDO)voltageregulatorsistailoredtonoise-sensitiveandRFappli-cations.Theseproductsfeaturedual250mALDOswithultralownoise,highpower-supplyrejectionratio(PSRR),andfasttransientandstart-upresponse.Eachregulatoroutputisstablewithlow-cost2.2µFceramicoutputcapacitorsandfeaturesverylowdropoutvoltages(125mVtypicalat250mA).Eachregulatorachievesfaststart-uptimes(approximately60µswitha0.001µFbypasscapacitor)whileconsumingverylowquiescentcurrent(300µAtypicalwithbothoutputsenabled).Whenthedeviceisplacedinstandbymode,thesupplycurrentisre-ducedtolessthan0.3µAtypical.Eachregulatorexhibitsapproximately32µVrmsofoutputvoltagenoisewithVOUT=2.8Vanda0.01µFnoisereduction(NR)capacitor.Applicationswithanalogcomponentsthatarenoise-sensitive,suchasport-ableRFelectronics,willbenefitfromhighPSRR,lownoise,andfastlineandloadtransientfeatures.TheTPS712familyisofferedinathin3mmx3mmSONpackageandisfullyspecifiedfrom-40°Cto+125°C(TJ).
APPLICATIONS
•••••
CellularandCordlessPhonesWirelessPDA/HandheldProductsPCMCIA/WirelessLANApplications
DigitalCamera/Camcorder/InternetAudioDSP/FPGA/ASIC/ControllersandProcessors
PSRR(RIPPLEREJECTION)vsFREQUENCY
8070
DRC PACKAGE3mm x 3mm SON(TOP VIEW)IN1NC2OUT13OUT24GND510EN19FB1/NC8EN27FB2/NC6NR
60PSRR(dB)5040302010010
VOUT=2.8VCOUT=2.2µFCNR=0.01µF100
1k
10k
100k
1M
10M
IOUT=1mAIOUT=250mAFrequency(Hz)
Pleasebeawarethatanimportantnoticeconcerningavailability,standardwarranty,anduseincriticalapplicationsofTexasInstrumentssemiconductorproductsanddisclaimerstheretoappearsattheendofthisdatasheet.
PRODUCTIONDATAinformationiscurrentasofpublicationdate.ProductsconformtospecificationsperthetermsoftheTexasInstrumentsstandardwarranty.Productionprocessingdoesnotnecessarilyincludetestingofallparameters.
Copyright©2004–2005,TexasInstrumentsIncorporated
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ThisintegratedcircuitcanbedamagedbyESD.TexasInstrumentsrecommendsthatallintegratedcircuitsbehandledwithappropriateprecautions.Failuretoobserveproperhandlingandinstallationprocedurescancausedamage.
ESDdamagecanrangefromsubtleperformancedegradationtocompletedevicefailure.Precisionintegratedcircuitsmaybemoresusceptibletodamagebecauseverysmallparametricchangescouldcausethedevicenottomeetitspublishedspecifications.
ORDERINGINFORMATION(1)
VOLTAGE(TJ)PRODUCTTPS71202TPS71219TPS71229TPS71247TPS71256TPS71257(1)
VOUT1Adjustable1.8V2.8V1.8V2.8V2.85VVOUT2AdjustableAdjustableAdjustable2.85V2.8V2.85VPACKAGE-LEAD(DESIGNATOR)SON-10(DRC)SON-10(DRC)SON-10(DRC)SON-10(DRC)SON-10(DRC)SON-10(DRC)SPECIFIEDTEMPERATURERANGE(TJ)-40°Cto+125°C-40°Cto+125°C-40°Cto+125°C-40°Cto+125°C-40°Cto+125°C-40°Cto+125°CPACKAGEMARKINGARQARWARUARSARVARTORDERINGNUMBERTPS71202DRCTTPS71202DRCRTPS71219DRCTTPS71219DRCRTPS71229DRCTTPS71229DRCRTPS71247DRCTTPS71247DRCRTPS71256DRCTTPS71256DRCRTPS71257DRCTTPS71257DRCRTRANSPORTMEDIA,QUANTITYTapeandReel,250TapeandReel,3000TapeandReel,250TapeandReel,3000TapeandReel,250TapeandReel,3000TapeandReel,250TapeandReel,3000TapeandReel,250TapeandReel,3000TapeandReel,250TapeandReel,3000Forthemostcurrentpackageandorderinginformation,seethePackageOrderingAddendumlocatedattheendofthisdatasheet.
ABSOLUTEMAXIMUMRATINGS
overoperatingjunctiontemperaturerangeunlessotherwisenoted(1)
TPS712xx
VINrangeVEN1,VEN2rangeVOUTrangePeakoutputcurrentOutputshort-circuitdurationContinuoustotalpowerdissipationJunctiontemperaturerange,TJStoragetemperaturerangeESDrating,HBMESDrating,CDM(1)
-0.3to6.0-0.3toVIN+0.3-0.3to6.0Internallylimited
Indefinite
SeeDissipationRatingsTable-40to+150-65to+150
2500
°C°CkVVUNITVVV
Stressesbeyondthoselistedunderabsolutemaximumratingsmaycausepermanentdamagetothedevice.Thesearestressratingsonly,andfunctionaloperationofthedeviceattheseoranyotherconditionsbeyondthoseindicatedundertheElectricalCharacteristicsisnotimplied.Exposuretoabsolutemaximumratedconditionsforextendedperiodsmayaffectdevicereliability.
POWERDISSIPATIONRATINGS
BOARDHigh-K(1)(1)
PACKAGEDRC
RθJC48
RθJA52
DERATINGFACTORABOVETA=25°C
19mW/°C
TA≤25°CPOWERRATING
1.92W
TA=70°CPOWERRATING
1.06W
TA=85°CPOWERRATING
0.77W
TheJEDECHigh-K(2s2p)boarddesignusedtoderivethisdatawasa3inchx3inch,multilayerboardwith1-ounceinternalpowerandgroundplanesand2-ouncecoppertracesonthetopandbottomoftheboard.
2
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ELECTRICALCHARACTERISTICS
Overoperatingtemperaturerange(TJ=-40°Cto+125°C),VIN=highestVOUT(nom)+1.0Vor2.7V(whicheverisgreater),IOUT=1mA,VEN1,2=1.2V,COUT=10µF,CNR=0.01µF,andadjustableLDOsaretestedatVOUT=3.0V,unlessotherwisenoted.TypicalvaluesareatTJ=25°C.
PARAMETER
VINVFB
Inputvoltagerange(1)
Internalreference(adjustableLDOs)Outputvoltagerange(adjustableLDOs)
VOUT
Accuracy(1)
∆VOUT%/∆VIN∆VOUT%/∆IOU
T
TESTCONDITIONSMIN2.71.200VFB
TYP1.225
MAX5.51.250
UNITVVV
5.5-VDO
+1.5
±10.050.8125
230800250+3
NominalOverVIN,IOUT,andT
TJ=25°C,IOUT=0mAVOUT+1.0V≤VIN≤5.5V,0µA≤IOUT≤250mAVOUT+1.0V≤VIN≤5.5V0µA≤IOUT≤250mA
-1.5-3
%%/V%/mAmVmA
Lineregulation(1)LoadregulationDropoutvoltage(2)
(VIN=VOUT(nom)-0.1V)Outputcurrentlimit
OneLDOenabledBothLDOsenabled2.8V,2.85VAdjustable
VDOICLIGNDISHDNIFBVnPSRRtSTRVIHVILIENTSDUVLO
IOUT1=IOUT2=250mAVOUT=0.9×VOUT(nom)
IOUT=1mA(enabledchannel)IOUT1=IOUT2=1mAto250mAVEN≤0.4V,0V≤VIN≤5.5VNoCNR,IOUT=250mACNR=0.01µF,IOUT=250mAf=100Hz,IOUT=250mAf=10kHz,IOUT=250mA
VOUT=2.85V,RL=30Ω,CNR=0.001µF
1.20
VIN=VEN=5.5VShutdownResetVINrisingVINfalling
TempincreasingTempdecreasing
2.25-1400
6001903000.30.1
GroundpincurrentShutdowncurrent(3)
µA
6002.01
µAµAµVrmsdBµs
VIN0.41
+160+140
2.65
100
VVµA°CVmV
FBpincurrent(adjustableLDOs)Outputnoisevoltage,BW=10Hz-100kHzPower-supplyrejectionratio(ripplerejection)Startuptime
Enablethresholdhigh(EN1,EN2)Enablethresholdlow(EN1,EN2)Enablepincurrent(EN1,EN2)ThermalshutdowntemperatureUndervoltagelockoutthresholdUndervoltagelockouthysteresis
80.0×VOUT11.8×VOUT
656560
(1)(2)(3)
MinimumVIN=VOUT+VDOor2.7V,whicheverisgreater.
VDOisnotmeasuredfor1.8VregulatorssinceminimumVIN=2.7V.
Fortheadjustableversion,thisappliesonlyafterVINisapplied;thenVENtransitionsfromhightolow.
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FUNCTIONALBLOCKDIAGRAM—
FIXEDVERSION
INCurrentLimit30µAOUT1INFUNCTIONALBLOCKDIAGRAM—
ADJUSTABLEVERSION
OUT1CurrentLimit90 kΩEN1
ThermalShutdownOUT2UVLOCurrentLimit30µAEN1
ThermalShutdownFB1OUT2UVLOCurrentLimit90 kΩFB2EN2
250kΩVREF1.225VQuickstart5pFTPS712xxFixed/FixedNRVREF1.225VQuickstart5pFTPS712xxAdj/AdjEN2
250kΩNRTable1.TERMINALFUNCTIONS
TERMINALNAMEINGNDOUT1OUT2EN1EN2FB1/NCFB2/NCNRNC
DRC15,Pad3410762
Ground
Outputoftheregulator.Asmall2.2µFceramiccapacitorisrequiredfromthispintogroundtoassurestability.
SameasOUT1butforLDO2.
Drivingtheenablepin(EN)highturnsonLDO1.DrivingthispinlowputsLDO1intoshutdownmode,reducingoperatingcurrent.TheenablepinshouldbeconnectedtoINifnotused.SameasEN1butcontrolsLDO2.
FeedbackforCH1adjustableversion;noconnectionfornon-adjustableCH1.FeedbackforCH2adjustableversion;noconnectionfornon-adjustableCH2.
Noisereductionpin;connectanexternalbypasscapacitortoreduceLDOoutputnoise.Noconnection.
DESCRIPTION
Unregulatedinputsupply.Asmall0.1µFcapacitorshouldbeconnectedfromINtoGND.
4
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TYPICALCHARACTERISTICS
ForallvoltageversionsatTJ=25°C,VIN=VOUT(nom)+1V,IOUT=1mA,VEN=1.2V,COUT=2.2µF,andCNR=0.01µF,
unlessotherwisenoted.
OUTPUTVOLTAGEvsINPUTVOLTAGE
1.00.80.60.4VOUT(%)0.20−0.2−0.4−0.6−0.8−1.0
3.0
3.5
4.0
4.5VIN(V)
5.0
5.5
6.0
−40_C+125_C+25_CVOUT(%)1.00.80.60.40.20−0.2−0.4−0.6−0.8−1.0
0
50
100
150
200
250
IOUT(mA)
+125_C+25_C−40_COUTPUTVOLTAGEvsOUTPUTCURRENT
Figure1.Figure2.
DROPOUTVOLTAGEvsINPUTVOLTAGE
(ADJUSTABLEVERSION)
200180
OUTPUTVOLTAGEvsTEMPERATURE
1.0
0.5160DropoutVoltage(mV)IOUT=10mA14012010080604020
TJ=−40_CTJ=+125_CTJ=+25_CVOUT(%)0
IOUT=125mA−0.5−1.0
−1.5
−40−25−10
IOUT=250mA0
5
20
35
50
65
80
95
110125
2.7
2.9
3.1
3.3
3.5
3.7
3.94.1
4.3
4..7
4.9
JunctionTemperature(_C)
VIN(V)
Figure3.
TPS71256
DROPOUTVOLTAGEvsOUTPUTCURRENT
200
TJ=+125_CDropoutVoltage(mV)DropoutVoltage(mV)150
200
Figure4.
TPS71256
DROPOUTVOLTAGEvsJUNCTIONTEMPERATURE
250
150
IOUT=250mA100
100
TJ=+25_C50
TJ=−40_C50
00
50
100
150
200
250
IOUT(mA)
0
−40−25−10
5203550658095110125
Junction Temperature (°C)
Figure5.Figure6.
5
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TYPICALCHARACTERISTICS(continued)
ForallvoltageversionsatTJ=25°C,VIN=VOUT(nom)+1V,IOUT=1mA,VEN=1.2V,COUT=2.2µF,andCNR=0.01µF,unlessotherwisenoted.
GROUNDPINCURRENTvsINPUTVOLTAGE
400375350IGND(µA)IGND(µA)325300275250225200
2.7
3.2
3.7
4.2VIN(V)
4.7
5.2
5.7
+25_C−40_C+125_C400375350325
+125_C300275250225200
0
50
100
150
200
250
IOUT(mA)
−40_C+25_CGROUNDPINCURRENTvsIOUT
Figure7.Figure8.
GROUNDPINCURRENTvsJUNCTIONTEMPERATURE
(DISABLED)
500
VEN1=VEN2=1.2VVIN=3.8V450400350IGND(nA)300250200150100500
VEN1=VEN2=0.4VVIN=3.8VGROUNDPINCURRENTvsJUNCTIONTEMPERATURE
400375350IGND(µA)325300275250225200
−40−25−10
5
20
35
50
65
80
95
110125
JunctionTemperature(_C)
−40−25−105203550658095110125
JunctionTemperature(_C)
Figure9.Figure10.
TPS71256
LINETRANSIENTRESPONSE
COUT1=COUT2=10µF3.8V
VIN
3.2V
CURRENTLIMITvsJUNCTIONTEMPERATURE
800750CurrentLimit(mA)700650600550500450
400
−40−25−10
10mV/div
VIN=3.8VIOUT=250mAIOUT=1mAVOUT1
10mV/divVOUT2
5203550658095110125
100µs/div
JunctionTemperature(_C)
Figure11.Figure12.
6
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TYPICALCHARACTERISTICS(continued)
ForallvoltageversionsatTJ=25°C,VIN=VOUT(nom)+1V,IOUT=1mA,VEN=1.2V,COUT=2.2µF,andCNR=0.01µF,unlessotherwisenoted.
TPS71256
LOADTRANSIENTRESPONSE
ANDVOUT2CROSSTALK
2mV/div
COUT2=10µFVOUT2
TPS71256
CHANNEL-TO-CHANNELISOLATIONvsFREQUENCY
6050ChannelIsolation(dB)403020100
COUT1=COUT2=10µFIOUT1=0mAto500mASinusoidalLoadIOUT2=25mA0.1
1
10Frequency(Hz)
100
1k
100mV/div
COUT1=10µFVOUT1
250mA10mA200mA/div
IOUT1
20µs/div
Figure13.
TPS71256
TURN-ON/OFFRESPONSEANDVOUT2CROSSTALK
CNR=0.01µF20mV/div
CNR=0.001µFIOUT1=IOUT2=250mACOUT1=COUT2=10µFVOUT2
Figure14.
TPS71229
POWER-UP/POWER-DOWN
IOUT1=IOUT2=250mAVIN1V/divVOUT1VOUT21V/div
VOUT1VEN1
50µs/div
50ms/div
Figure15.Figure16.
NOISESPECTRALDENSITY
COUT=2.2µF
SpectralNoiseDensity(nV/√Hz)VOUT=2.8V350300250200150100500100
IOUT=1mAIOUT=250mACNR=0.1µFVOUT=2.8VTOTALNOISEvsCNR
250
COUT=2.2µFIOUT=250mACOUT=2.2µFIOUT=0mA200TotalNoise(µVrms)COUT=10µFIOUT=250mA150
100
COUT=10µFIOUT=0mA50
0
110100
CNR(pF)
1k10k100k1k
Frequency(Hz)
10k100k
Figure17.Figure18.
7
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TYPICALCHARACTERISTICS(continued)
ForallvoltageversionsatTJ=25°C,VIN=VOUT(nom)+1V,IOUT=1mA,VEN=1.2V,COUT=2.2µF,andCNR=0.01µF,unlessotherwisenoted.
NOISESPECTRALDENSITY
COUT=10µF
350SpectralNoiseDensity(nV/√Hz)300250200150100500100
IOUT=1mAIOUT=250mASpectralNoiseDensity(nV/√Hz)CNR=0.01µFVOUT=2.8V180160140120100806040200100
1k
Frequency(Hz)
10k
100k
0.1µF0.047µF0.01µF0.001µFNOISESPECTRALDENSITYvsCNR
COUT=10µFIOUT=250mAVOUT=2.8V1k
Frequency(Hz)
10k100k
Figure19.
PSRR(RIPPLEREJECTION)vsFREQUENCY
807060PSRR(dB)PSRR(dB)50403020100
VOUT=2.8VCOUT=2.2µFCNR=0.01µF10
100
1k
10k
100k
1M
10M
IOUT=1mAIOUT=250mA8070605040302010010
Frequency(Hz)
VOUT=2.8VCOUT=10µFCNR=0.01µF100
1k
Figure20.
PSRR(RIPPLEREJECTION)vsFREQUENCY
IOUT=1mAIOUT=250mA10k100k1M10M
Frequency(Hz)
Figure21.
PSRR(RIPPLEREJECTION)vsVIN-VOUT
8070
f=1kHz60PSRR(dB)504030201000
0.2
0.4
0.6
0.8
1.0
1.2
1.4
VIN−VOUT(V)f=100kHzVOUT=2.8VIOUT=250mACOUT=10µFCNR=0.01µF1.6
1.8
2.0
f=10kHzFigure22.
Figure23.
8
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APPLICATIONINFORMATION
TheTPS712xxfamilyofduallow-dropout(LDO)regulatorshasbeenoptimizedforuseinnoise-sensitivebattery-operatedequipment.Thede-vicefeaturesextremelylowdropout,highPSRR,ultralowoutputnoise,andlowquiescentcurrent(190µAtypicalperchannel).Whenbothoutputsaredisabled,thesupplycurrentsarereducedtolessthan2µA.AtypicalapplicationcircuitisshowninFig-ure24.TPS712xx
VININOUT1VOUT1
2.2µFEN1EN2GNDOUT2NR0.01µFVOUT2
2.2µF1.8Vorlessischosen,theminimumrecommendedoutputcapacitoris4.7µF.Anyceramiccapacitorthatmeetstheminimumoutputcapacitorrequirementsissuitable.CapacitorswithhigherESRmaybeused,providedtheESRislessthan1Ω.
OUTPUTNOISE
TheinternalvoltagereferenceisakeysourceofnoiseinanLDOregulator.TheTPS712xxhasanNRpinthatisconnectedtothevoltagereferencethrougha250kΩinternalresistor.The250kΩinternalresistor,inconjunctionwithanexternalceramicbypasscapacitorconnectedtotheNRpin,createsalow-passfiltertoreducethevoltagereferencenoiseand,therefore,thenoiseattheregulatoroutput.Toachieveafaststartup,the250kΩinternalresistorisshortedfor400µsafterthedeviceisenabled.Becausetheprimarynoisesourceistheinternalvoltagereference,theoutputnoisewillbegreaterforhigheroutputvoltageversions.Forthecasewherenonoisereductioncapacitorisused,thetypicalnoise(µVrms)over10Hzto100kHzis80timestheoutputvoltage.Ifa0.01µFcapacitorisusedfromtheNRpintoground,thenoise(µVrms)dropsto11.8timestheoutputvoltage.Forexample,theTPS71256exhibitsonly33µVrmsofoutputvoltagenoiseusinga0.01µFceramicbypasscapacitoranda2.2µFceramicoutputcapacitor.
0.1µFFigure24.TypicalApplicationCircuit
(fixed-voltageversions)
INPUTANDOUTPUTCAPACITORREQUIREMENTS
A0.1µForlargerceramicinputbypasscapacitor,connectedbetweenINandGNDandlocatedclosetotheTPS712xx,isrequiredforstability.Itimprovestransientresponse,noiserejection,andripplerejec-tion.Ahigher-valueinputcapacitormaybenecessaryiflarge,fast-rise-timeloadtransientsareanticipatedandthedeviceislocatedseveralinchesfromthepowersource.
TheTPS712xxrequiresanoutputcapacitorconnec-tedbetweentheoutputsandGNDtostabilizetheinternalcontrolloops.Theminimumrecommendedoutputcapacitoris2.2µF.Ifanoutputvoltageof
STARTUPCHARACTERISITCS
Tominimizestartupovershoot,theTPS712xxwillinitiallytargetanoutputvoltagethatisapproximately80%ofthefinalvalue.Toavoidadelayedstartuptime,noisereductioncapacitorsof0.01µForlessarerecommended.Largernoisereductioncapacitorswillcausetheoutputtoholdat80%untilthevoltageonthenoisereductioncapacitorexceeds80%ofthebandgapvoltage.Thetypicalstartuptimewitha0.001µFnoisereductioncapacitoris60µs.Onceoneoftheoutputvoltagesispresent,thestartuptimeoftheotheroutputwillnotbeaffectedbythenoisereductioncapacitor.
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PROGRAMMINGTHETPS71202ADJUSTABLELDOREGULATOR
TheoutputvoltageoftheTPS71202dualadjustableregulatorisprogrammedusinganexternalresistordivider,asshowninFigure25.TheoutputvoltageiscalculatedusingEquation1:
VOUT+VREF 1)R1
R2
C1+
(3 105) (R1)R2)
(R1 R2)
(pF)
(3)
ǒǓ(1)
ThesuggestedvalueofthiscapacitorforseveralresistorratiosisshowninFigure25.Ifthiscapacitorisnotused(suchasinaunity-gainconfiguration)orifanoutputvoltage≤1.8Vischosen,thentheminimumrecommendedoutputcapacitoris4.7µFinsteadof2.2µF.
whereVREF=1.225V(theinternalreferencevolt-age).
ResistorsR2andR4shouldbechosenforapproxi-matelya40µAdividercurrent.Lowervalueresistorscanbeusedforimprovednoiseperformance,butwillconsumemorepower.HighervaluesshouldbeavoidedbecauseleakagecurrentatFBincreasestheoutputvoltageerror.Therecommendeddesignpro-cedureistochooseR2=30.1kΩtosetthedividercurrentat40µA,andthencalculateR1usingEquation2:
R1+
DROPOUTVOLTAGE
TheTPS712xxusesaPMOSpasstransistortoachieveextremelylowdropout.When(VIN-VOUT)islessthanthedropoutvoltage(VDO),thePMOSpassdeviceisinitslinearregionofoperationandtheinput-to-outputresistanceistheRDS,ONofthePMOSpasselement.DropoutvoltagesatlowercurrentscanbeapproximatedbycalculatingtheeffectiveRDS,ONofthepasselementandmultiplyingthatresistancebytheloadcurrent.RDS,ONofthepasselementcanbeobtainedbydividingthedropoutvoltagebytheratedoutputcurrent.FortheTPS71256,theRDS,ONofthepasselementis84mΩ.ThedropoutvoltageoftheTPS712xxwillbelessforhigheroutputvoltageversions.ThisisbecausethePMOSpasselementwillhaveloweron-resistanceduetoincreasedgatedrive.
ǒVV
OUTREF
*1 R2
Ǔ
(2)
Toimprovethestabilityandnoiseperformanceoftheadjustableversion,asmallcompensationcapacitorcanbeplacedbetweenOUTandFB.
Forvoltages≤1.8V,thevalueofthiscapacitorshouldbe100pF.Forvoltages>1.8V,theapproxi-matevalueofthiscapacitorcanbecalculatedasEquation3:
TPS71202
VININOUT1R1EN1EN20.1µFOUT2R3NR0.01µFGNDFB2R4C22.2µFFB1R2C12.2µFVOUT1
Output Voltage Programming Guide
VOUT1.225 V1.5 V
R1/R3Short7.15 kΩ31.6 kΩ43.2 kΩ49.9 kΩ86.6 kΩ
R2/R4Open30.1 kΩ30.1 kΩ30.1 kΩ30.1 kΩ30.1 kΩ
C1/C2Open100 pF22 pF15 pF15 pF15 pF
VOUT22.5 V3.0 V3.3 V4.75 V
Figure25.TPS71202AdjustableLDORegulatorProgramming
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SBVS049B–MAY2004–REVISEDMARCH2005
TRANSIENTRESPONSE
Aswithanyregulator,increasingthesizeoftheoutputcapacitorwillreduceover/undershootmagni-tudebutincreasedurationofthetransientresponse.Intheadjustableversion,theadditionofacapacitor,CFB,fromtheoutputtothefeedbackpinwillalsoimprovestabilityandtransientresponse.Thetransi-entresponseoftheTPS712xxisenhancedwithanactivepull-downthatengageswhentheoutputisover-voltaged.Theactivepull-downdecreasestheoutputrecoverytimewhentheloadisremoved.Figure13intheTypicalCharacteristicssectionshowstheoutputtransientresponse.
Dependingonpowerdissipation,thermalresistance,andambienttemperature,thethermalprotectioncircuitmaycycleonandoff.Thislimitsthedissipationoftheregulator,protectingitfromdamageduetooverheating.
Anytendencytoactivatethethermalprotectioncircuitindicatesexcessivepowerdissipationoraninad-equateheatsink.Forreliableoperation,junctiontem-peratureshouldbelimitedto+125°Cmaximum.Toestimatethemarginofsafetyinacompletedesign(includingheatsink),increasetheambienttempera-tureuntilthethermalprotectionistriggered;useworst-caseloadsandsignalconditions.Forgoodreliability,thermalprotectionshouldtriggeratleast+35°Cabovethemaximumexpectedambientcon-ditionofyourapplication.Thisproducesaworst-casejunctiontemperatureof+125°Catthehighestex-pectedambienttemperatureandworst-caseload.TheinternalprotectioncircuitryoftheTPS712xxwasdesignedtoprotectagainstoverloadconditions.Itwasnotintendedtoreplaceproperheatsinking.ContinuouslyrunningtheTPS712xxintothermalshutdownwilldegradedevicereliability.
SHUTDOWN
BothenablepinsareactivehighandarecompatiblewithstandardTTL-CMOSlevels.ThedeviceisonlycompletelydisabledwhenbothEN1andEN2arelogiclow.Inthisstate,theLDOiscompletelyoffandthegroundpincurrentdropstoapproximately100nA.Withoneoutputdisabled,thegroundpincurrentisslightlygreaterthanhalfthenominalvalue.Whenshutdowncapabilityisnotrequired,theenablepinsshouldbeconnectedtotheinputsupply.
POWERDISSIPATION
Theabilitytoremoveheatfromthedieisdifferentforeachpackagetype,presentingdifferentconsider-ationsinthePCBlayout.ThePCBareaaroundthedevicethatisfreeofothercomponentsmovestheheatfromthedevicetotheambientair.PerformancedataforaJEDEChigh-KboardisshownintheDissipationRatingstable.Usingheaviercopperwillincreasetheeffectivenessinremovingheatfromthedevice.Theadditionofplatedthrough-holestoheat-dissipatinglayerswillalsoimprovetheheat-sinkeffectiveness.
Powerdissipationdependsoninputvoltageandloadconditions.Powerdissipationisequaltotheproductoftheoutputcurrenttimesthevoltagedropacrosstheoutputpasselement(VINtoVOUT):PD+(VIN*VOUT) IOUT
(4)Powerdissipationcanbeminimizedbyusingthelowestpossibleinputvoltagenecessarytoassuretherequiredoutputvoltage.
INTERNALCURRENTLIMIT
TheTPS712xxinternalcurrentlimithelpsprotecttheregulatorduringfaultconditions.Duringcurrentlimit,theoutputwillsourceafixedamountofcurrentthatislargelyindependentoftheoutputvoltage.
TheTPS712xxPMOS-passtransistorshaveabuilt-inbackdiodethatconductsreversecurrentwhentheinputvoltagedropsbelowtheoutputvoltage(thatis,duringpower-down).Currentisconductedfromtheoutputtotheinputandisnotinternallylimited.Ifextendedreversevoltageoperationisanticipated,externallimitingmaybeappropriate.
THERMALPROTECTION
Thermalprotectiondisablesbothoutputswhenthejunctiontemperatureofeitherchannelrisestoap-proximately+160°C,allowingthedevicetocool.Whenthejunctiontemperaturecoolstoapproxi-mately+140°C,theoutputcircuitryisagainenabled.
11
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PACKAGEOPTIONADDENDUM
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PACKAGINGINFORMATION
OrderableDeviceTPS71202DRCRTPS71202DRCRG4TPS71202DRCTTPS71219DRCRTPS71219DRCRG4TPS71219DRCTTPS71229DRCRTPS71229DRCRG4TPS71229DRCTTPS71229DRCTG4TPS71247DRCRTPS71247DRCRG4TPS71247DRCTTPS71256DRCRTPS71256DRCTTPS71257DRCRTPS71257DRCRG4TPS71257DRCT
(1)
Status(1)ACTIVEACTIVEACTIVEACTIVEACTIVEACTIVEACTIVEACTIVEACTIVEACTIVEACTIVEACTIVEACTIVEPREVIEWPREVIEWACTIVEACTIVEACTIVE
PackageTypeSONSONSONSONSONSONSONSONSONSONSONSONSONSONSONSONSONSON
PackageDrawingDRCDRCDRCDRCDRCDRCDRCDRCDRCDRCDRCDRCDRCDRCDRCDRCDRCDRC
PinsPackageEcoPlan(2)
Qty101010101010101010101010101010101010
3000Green(RoHS&
noSb/Br)3000Green(RoHS&
noSb/Br)250
Green(RoHS&noSb/Br)
Lead/BallFinishCUNIPDAUCUNIPDAUCUNIPDAUCUNIPDAUCUNIPDAUCUNIPDAUCUNIPDAUCUNIPDAUCUNIPDAUCUNIPDAUCUNIPDAUCUNIPDAUCUNIPDAUCallTICallTICUNIPDAUCUNIPDAUCUNIPDAU
MSLPeakTemp(3)Level-2-260C-1YEARLevel-2-260C-1YEARLevel-2-260C-1YEARLevel-2-260C-1YEARLevel-2-260C-1YEARLevel-2-260C-1YEARLevel-2-260C-1YEARLevel-2-260C-1YEARLevel-2-260C-1YEARLevel-2-260C-1YEARLevel-2-260C-1YEARLevel-2-260C-1YEARLevel-2-260C-1YEARCallTICallTI
Level-2-260C-1YEARLevel-2-260C-1YEARLevel-2-260C-1YEAR
3000Green(RoHS&
noSb/Br)3000Green(RoHS&
noSb/Br)250
Green(RoHS&noSb/Br)
3000Green(RoHS&
noSb/Br)3000Green(RoHS&
noSb/Br)250250
Green(RoHS&noSb/Br)Green(RoHS&noSb/Br)
3000Green(RoHS&
noSb/Br)3000Green(RoHS&
noSb/Br)2503000250
Green(RoHS&noSb/Br)
TBDTBD
3000Green(RoHS&
noSb/Br)3000Green(RoHS&
noSb/Br)250
Green(RoHS&noSb/Br)
Themarketingstatusvaluesaredefinedasfollows:ACTIVE:Productdevicerecommendedfornewdesigns.
LIFEBUY:TIhasannouncedthatthedevicewillbediscontinued,andalifetime-buyperiodisineffect.
NRND:Notrecommendedfornewdesigns.Deviceisinproductiontosupportexistingcustomers,butTIdoesnotrecommendusingthispartinanewdesign.
PREVIEW:Devicehasbeenannouncedbutisnotinproduction.Samplesmayormaynotbeavailable.OBSOLETE:TIhasdiscontinuedtheproductionofthedevice.
(2)
EcoPlan-Theplannedeco-friendlyclassification:Pb-Free(RoHS)orGreen(RoHS&noSb/Br)-pleasecheckhttp://www.ti.com/productcontentforthelatestavailabilityinformationandadditionalproductcontentdetails.TBD:ThePb-Free/Greenconversionplanhasnotbeendefined.
Pb-Free(RoHS):TI'sterms\"Lead-Free\"or\"Pb-Free\"meansemiconductorproductsthatarecompatiblewiththecurrentRoHSrequirementsforall6substances,includingtherequirementthatleadnotexceed0.1%byweightinhomogeneousmaterials.Wheredesignedtobesolderedathightemperatures,TIPb-Freeproductsaresuitableforuseinspecifiedlead-freeprocesses.
Green(RoHS&noSb/Br):TIdefines\"Green\"tomeanPb-Free(RoHScompatible),andfreeofBromine(Br)andAntimony(Sb)basedflameretardants(BrorSbdonotexceed0.1%byweightinhomogeneousmaterial)
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(3)
MSL,PeakTemp.--TheMoistureSensitivityLevelratingaccordingtotheJEDECindustrystandardclassifications,andpeaksoldertemperature.
ImportantInformationandDisclaimer:TheinformationprovidedonthispagerepresentsTI'sknowledgeandbeliefasofthedatethatitisprovided.TIbasesitsknowledgeandbeliefoninformationprovidedbythirdparties,andmakesnorepresentationorwarrantyastotheaccuracyofsuchinformation.Effortsareunderwaytobetterintegrateinformationfromthirdparties.TIhastakenandcontinuestotakereasonablestepstoproviderepresentativeandaccurateinformationbutmaynothaveconducteddestructivetestingorchemicalanalysisonincomingmaterialsandchemicals.TIandTIsuppliersconsidercertaininformationtobeproprietary,andthusCASnumbersandotherlimitedinformationmaynotbeavailableforrelease.
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