LM26资料
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LM2601
AdapterInterfaceCircuit
GeneralDescription
TheAdapterInterfaceCircuit(AIC)isusedtosensethe
presenceofanexternalpowersourceforaportablecom-
puter.Itnotifiesthecomputerifasourceispresentand
indicatesifthesourceisappropriateforchargingbattery
packsinsidethecomputer.TheAICalsosensesanadapter
currentanditsdirection.AICisolatestheadapterandsignals
thecomputerwhenpeakcurrentthresholdisexceeded.
LM2601drivesP-channelFETs.Nohighcurrentrated
Schottkydiodeisrequiredtoimplementanadapterswitcho-
vercircuit.Thissignificantlydecreasesadditionalheatdissi-
pationduringsimultaneousfastbatterychargingwhilerun-
ningacomputer,particularlyinMaximumPerformance
modeofoperation
Features
nDetectsanAC-DCadaptersuitableforbatterycharging
oranairplaneorcarpowerlineadapterthatshouldnot
beusedforbatterycharging
nAllowstheimplementationofintelligentswitchover
circuitsforportablesystemsnLM2601shutsdownautomaticallywhenadapteris
removed
nLowleakagecurrentfrombatterywhennotpowered
nDrivesP-channelFETs,noSchottkydiodesarerequired
nNoreverseinrushcurrentfrombatteryintotheadapter
outputcapacitance
nAllowsforbatterycapacitygas-gaugecalibrationunder
systemsoftware/firmwarecontrol
nAdapterovercurrentthresholdprogrammablewith
externalresistors
nWideinputrange:5V-24V
nAvailableinTSSOP-14package
Applications
nPortableComputers
nPortableIAs(InternetAppliances,Information
Appliances)
nOtherBatteryPoweredDevices
BlockDiagram
10130901April2001LM2601
Adapter
Interface
Circuit
©2001NationalSemiconductorCorporationDS101309www.national.com元器件交易网www.cecb2b.comPinConfiguration
TSSOP-14
10130902
OrderingInformation
OrderNumberPackageNumberPackageTypeSuppliedAs*
LM2601MTCMTC14TSSOP-14Rail(94Units/Rail)
LM2601MTCXMTC14TSSOP-14TapeandReel(2500
Units/Reel)
*PartialRailsareavailable,thereisnominimumorderquantity.TapeandReelissuppliedasfullreelsonly.
PinDescription
PinNo.NameFunction
1MPSDELAYAcapacitorbetweenthispinandgroundsetsthedelayoftheMPSrisetime.SeeMPS
DELAYdescriptioninTypicalApplicationsection.
2MASTERPOWER
SOURCEBi-directionallogicpin.Ifdrivenhighbyanexternalsource,indicatesthatabatteryis
poweringthepowerbus.IfdrivenhighbytheAIC,indicatestheadapterispoweringthe
bus.AICcannotdriveMPSlow.Ifthereisnovalidadaptervoltagepresent,thepinisnot
anoutputbutahighimpedancelogicinput.Theinputispulled-downviaaninternal40k
resistor.
3ADAPTER
ENABLELogicinputpin.Activehigh.Grantspermissiontotheadaptertodriveboththepowerbus
andtheMPSsignal.
4ADAPTER
PRESENTLogicoutputpin.Highwhen12volts
pull-downresistor.Thesourcecurrentisnotinternallylimitedandthepartcanbe
damagediftheoutputisshortedtogroundwhendrivenHIGH.
5CHARGER
PRESENTLogicoutputpin.HighwhenVADAPTER>17volts.Theoutputtypicallyhas40kpull-down
resistor.Thesourcecurrentisnotinternallylimitedandthepartcanbedamagedifthe
outputisshortedtogroundwhendrivenHIGH.
9GNDICgroundpin.
10DISCONNECTDrivesthegateofthedisconnectP-chFET.
11BACKFEEDDrivesthegateofthebackfeedP-chFET.
12DIRECTION
SENSEConnectionforcurrentsenseresistortocontrolBACKFEED.
13PEAKSENSEConnectionforcurrentsenseresistortocontrolDISCONNECT.
14VADAPTERPowerinputpin.OutputofACadapter,autoadapterorairlineadapter.LM2601
www.national.com2元器件交易网www.cecb2b.comAbsoluteMaximumRatings(Note1)
IfMilitary/Aerospacespecifieddevicesarerequired,
pleasecontacttheNationalSemiconductorSalesOffice/
Distributorsforavailabilityandspecifications.
VADAPTER−0.3Vto28V
VPEAKSENSE,VDIRECTIONSENSE,
VBACKFEED,VDISCONNECT−0.3VtoVADAPTERVADAPTERENABLE,
VMASTERPOWERSOURCE−0.3Vto5.5V
VMPSDELAY−0.3Vto2VStorageTemperature−40˚Cto125˚C
ESDRatings
HumanBodyModel(Note2)
MachineModel(Note3)2kV
200V
OperatingRatings(Note1)
SupplyVoltage(VADAPTER)5Vto24V
AmbientTemp.Range−20˚Cto70˚C
JunctionTemp.Range−20˚Cto85˚C
ElectricalCharacteristics
LimitswithstandardtypefaceapplyforTJ=25˚C,andlimitsinboldfacetypeapplyoverthefulltemperaturerange(Note4)
SymbolParameterConditionsMinTypMaxUnits
VAEAdapterEnable-
3V-or5V-CMOSorTTLLogicInputHigh
Low2.0
0.8V
VAP,CPLogicOutputVoltage
Adapterpresent,ChargerpresentHigh
Low,ISINK=5µA2.93.1
0.250.6V
VMPSIMasterPowerSource
5V-CMOSLogicInputHigh
Low4.0
0.8V
VMPSOLogicOutputVoltage
MasterPowerSourceVADAPTER>5.8V
High
Low4.54.75
0.050.5V
VADAPTERAdapterVoltageforVAPLow-to-High
Transition11.712.012.3
V
Hysteresis1.82.02.2
VCHARGERAdapterVoltageforVCPLow-to-HighTransition16.517.017.4
V
Hysteresis0.080.100.12
∆VBACKFEEDCurrentSenseDifferentialVoltage
ThresholdforDrivingBackfeedFETVadapter−Directionsense,
VADAPTER=5V4
3917
18mV
∆VDISCONNECTCurrentSenseDifferentialVoltage
ThresholdforDrivingDisconnectFETVadapter−Peaksense,
VADAPTER=24V127
125135143
145mV
VBACKFEED,FETControlVoltageVADAPTER>11V
HighVADAPTER-
0.5V
VVDISCONNECTVADAPTER>11V
LowVADAPTER-
10Vor
GND+0.5V,
whicheveris
greater
tDRIVERise/FallTimeofFETDrive
(Note5)VADAPTER=10V
