300mA的超低噪声小封装超高速CMOS LDO稳压器LP3984.docx
《300mA的超低噪声小封装超高速CMOS LDO稳压器LP3984.docx》由会员分享,可在线阅读,更多相关《300mA的超低噪声小封装超高速CMOS LDO稳压器LP3984.docx(12页珍藏版)》请在冰豆网上搜索。
![300mA的超低噪声小封装超高速CMOS LDO稳压器LP3984.docx](https://file1.bdocx.com/fileroot1/2023-4/21/1e480ab0-c1a5-4e07-b3d2-2a9f06085e06/1e480ab0-c1a5-4e07-b3d2-2a9f06085e061.gif)
300mA的超低噪声小封装超高速CMOSLDO稳压器LP3984
300mA,Ultra-lownoise,SmallPackage
Ultra-FastCMOSLDORegulator
GeneralDescription
TheLP3984isdesignedforportableRFandwirelessapplicationswithdemandingperformanceandspacerequirements.TheLP3984performanceisoptimizedforbattery-poweredsystemstodeliverultralownoiseandlowquiescentcurrent.Anoisebypasspinisavailableforfurtherreductionofoutputnoise.Regulatorgroundcurrentincreasesonlyslightlyindropout,furtherprolongingthebatterylife.TheLP3984alsoworkswithlow-ESRceramiccapacitors,reducingtheamountofboardspacenecessaryforpowerapplications,criticalinhand-heldwirelessdevices.TheLP3984consumeslessthan0.01µAinshutdownmodeandhasfastturn-ontimelessthan50µs.Theotherfeaturesincludeultralowdropoutvoltage,highoutputaccuracy,currentlimitingprotection,andhighripplerejectionratio.Itisavailableinthe5-leadofSOT23-5packages.
OrderingInformation
LP3984□□□□□
F:
Pb-Free
PackageType
B5:
SOT23-5
OutputVoltageType
12:
1.2V
13:
1.3V
15:
1.5V
18:
1.8V
25:
2.5V
28:
2.8V
2H:
2.85V
30:
3.0V
33:
3.3V
Features
◆Ultra-Low-NoiseforRFApplication
◆2V-6.5VInputVoltageRange
◆LowDropout:
200mV@300mA
◆1.2V,1.3V,1.5V,1.8V,2.5V,2.8V3.0Vand3.3VFixed
◆300mAOutputCurrent,550mAPeakCurrent
◆HighPSSR:
-73dBat1KHz
◆<0.01uAStandbyCurrentWhenShutdown
◆AvailableinSOT23-5Package
◆TTL-Logic-ControlledShutdownInput
◆Ultra-FastResponseinLine/Loadtransient
◆CurrentLimitingandThermalShutdownProtection
◆Quickstart-up(typically50uS)
TypicalApplicationCircuit
Applications
✧PortableMediaPlayers/MP3players
✧CellularandSmartmobilephone
✧LCD
✧DSCSensor
✧WirelessCard
PinConfigurations
SOT23-5
MarkingInformation
Device
Marking
Package
Shipping
LP3984
XXXX
SOT23-5
3K/REEL
FunctionalPinDescription
Pinnumber
PinName
PinFunction
1
VIN
PowerInputVoltage.
2
GND
Ground.
3
EN
ChipEnable(ActiveHigh).Notethatthispinishighimpedance.Thereshouldbeapulllow100kΩresistorconnectedtoGNDwhenthecontrolsignalisfloating.
4
BP
ReferenceNoiseBypass.
5
VOUT
OutputVoltage.
FunctionBlockDiagram
AbsoluteMaximumRatings
SupplyInputVoltage----------------------------------------------------------------------------------------------------------6.5V
PowerDissipation,PD@TA=25°C
SOT23-5-------------------------------------------------------------------------------------------------------------------400mW
PackageThermalResistance
SOT23-5,θJA----------------------------------------------------------------------------------------------------------250°C/W
LeadTemperature(Soldering,10sec.)-----------------------------------------------------------------------------260°C
StorageTemperatureRange-----------------------------------------------------------------------------−65°Cto150°C
ESDSusceptibility
HBM(HumanBodyMode)------------------------------------------------------------------------------------------------2kVMM(Machine-Mode)--------------------------------------------------------------------------------------------------------200V
RecommendedOperatingConditions
SupplyInputVoltage----------------------------------------------------------------------------------------------2.5Vto5.5V
ENInputVoltage-----------------------------------------------------------------------------------------------------0Vto5.5V
OperationJunctionTemperatureRange----------------------------------------------------------------−40°Cto125°C
OperationAmbientTemperatureRange-------------------------------------------------------------------−40°Cto85°C
ElectricalCharacteristics
(VIN=VOUT+1V,CIN=COUT=1µF,CBP=22nF,TA=25°C,unlessotherwisespecified)
Parameter
Symbol
TestConditions
Min
Typ.
Max
Units
OutputVoltageAccuracy
ΔVOUT
IOUT=1mA
−2
--
+2
%
OutputLoadingCurrent
ILOAD
VEN=VIN,VIN>2.5V
300
mA
CurrentLimit
ILIM
RLOAD=1Ω
360
400
mA
QuiescentCurrent
IQ
VEN≥1.2V,IOUT=0mA
75
130
μA
DropoutVoltage
VDROP
IOUT=200mA,VOUT>2.8V
120
150
mV
IOUT=300mA,VOUT>2.8V
200
260
LineRegulation
ΔVLINE
VIN=(VOUT+1V)to5.5V,IOUT=1mA
0.3
%
LoadRegulation
ΔLOAD
1mA0.6
%
StandbyCurrent
ISTBY
VEN=GND,Shutdown
0.01
1
μA
ENInputBiasCurrent
IIBSD
VEN=GNDorVIN
0.1
100
nA
ENThreshold
Logic-LowVoltage
VIL
VIN=3Vto5.5V,Shutdown
0.4
V
Logic-HighVoltage
VIH
VIN=3Vto5.5V,Start-Up
1.4
OutputNoiseVoltage
10Hzto100kHz,IOUT=200mACOUT=1µF
100
uVRMS
PowerSupply
f=100Hz
PSRR
−76
dB
RejectionRate
f=10kHz
COUT=1µF,
IOUT=10mA
−68
ThermalShutdownTemperature
TSD
165
°C
TypicalOperatingCharacteristics
ILoad=200mA
ApplicationsInformation
Likeanylow-dropoutregulator,theexternalcapacitorsusedwiththeLP3984mustbecarefullyselectedforregulatorstabilityandperformance.Usingacapacitorwhosevalueis>1µFontheLP3984inputandtheamountofcapacitancecanbeincreasedwithoutlimit.Theinputcapacitormustbelocatedadistanceofnotmorethan0.5inchfromtheinputpinoftheICandreturnedtoacleananalogground.Anygoodqualityceramicortantalumcanbeusedforthiscapacitor.ThecapacitorwithlargervalueandlowerESR(equivalentseriesresistance)providesbetterPSRRandline-transientresponse.TheoutputcapacitormustmeetbothrequirementsforminimumamountofcapacitanceandESRinallLDOsapplication.TheLP3984isdesignedspecificallytoworkwithlowESRceramicoutputcapacitorinspace-savingandperformanceconsideration.Usingaceramiccapacitorwhosevalueisatleast1µFwithESRis>25mΩontheLP3984outputensuresstability.TheLP3984stillworkswellwithoutputcapacitorofothertypesduetothewidestableESRrange.Figure1showsthecurvesofallowableESRrangeasafunctionofloadcurrentforvariousoutputcapacitorvalues.Outputcapacitoroflargercapacitancecanreducenoiseandimproveloadtransientresponse,stability,andPSRR.Theoutputcapacitorshouldbelocatednotmorethan0.5inchfromtheVOUTpinoftheLP3984andreturnedtoacleananalogground.
Start-upFunctionEnableFunction
TheLP3984featuresanLDOregulatorenable/disablefunction.ToassuretheLDOregulatorwillswitchon,theENturnoncontrollevelmustbegreaterthan1.4volts.TheLDOregulatorwillgointotheshutdownmodewhenthevoltageontheENpinfallsbelow0.4volts.Fortoprotectingthesystem,theLP3984haveaquick-dischargefunction.Iftheenablefunctionisnotneededinaspecificapplication,itmaybetiedtoVINtokeeptheLDOregulatorinacontinuouslyonstate.
BypassCapacitorandLowNoise
Connectinga22nFbetweentheBPpinandGNDpinsignificantlyreducesnoiseontheregulatoroutput,itiscriticalthatthecapacitorconnectionbetweentheBPpinandGNDpinbedirectandPCBtracesshouldbeasshortaspossible.ThereisarelationshipbetweenthebypasscapacitorvalueandtheLDOregulatorturnontime.DCleakageonthispincanaffecttheLDOregulatoroutputnoiseandvoltageregulationperformance.
ThermalConsiderations
ThermalprotectionlimitspowerdissipationinLP3984.Whentheoperationjunctiontemperatureexceeds165°C,theOTPcircuitstartsthethermalshutdownfunctionturnthepasselementoff.Thepasselementturnsonagainafterthejunctiontemperaturecoolsby30°C.Forcontinueoperation,donotexceedabsolutemaximumoperationjunctiontemperature125°C.
Thepowerdissipationdefinitionindeviceis:
PD=(VIN−VOUT)xIOUT+VINxIQ
ThemaximumpowerdissipationdependsonthethermalresistanceofICpackage,PCBlayout,therateofsurroundingsairflowandtemperaturedifferencebetweenjunctiontoambient.
Themaximumpowerdissipationcanbecalculatedbyfollowingformula:
PD(MAX)=(TJ(MAX)−TA)/θJA
Where
TJ(MAX)isthemaximumoperationjunctiontemperature125°C,TAistheambienttemperatureandtheθJAisthejunctiontoambientthermalresistance.ForrecommendedoperatingconditionsspecificationofLP3984,where
TJ(MAX)isthemaximumjunctiontemperatureofthedie(125°C)andTAisthemaximumambienttemperature.Thejunctiontoambientthermalresistance(θJAislayoutdependent)forSOT23-5packageis250°C/W.
PD(MAX)=(125°C−25°C)/250=400mW(SOT23-5)PD(MAX)=(125°C−25°C)/165=606mW(withPCBPAD)
ThemaximumpowerdissipationdependsonoperatingambienttemperatureforfixedTJ(MAX)andthermalresistanceθJA.
PackagingInformation