Datasheet

PinFunctionCodeDescriptions
BAT_LOW/BAT_GDPin
bq27510-G1
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RESCAP=No-loadrateofcompensationisappliedtothereservecapacitycalculation.Truewhenset.Defaultis0.
BAT_GDoverridebit.IfthegaugeentersHIBERNATEonlyduetothecellvoltage,theBAT_GDwillnot
BATG_OVR=negate.Truewhenset.Defaultis0.IfbothcurrentandvoltagearebelowtheHIBERNATEthresholds,the
voltageconditioncheckaboveisprecedentoverthecurrentconditioncheck
Pinfunctioncode(PFC)modeselection:PFC0,1,or2selectedby0/0,0/1,or1/0,respectively.Defaultis
PFC_CFG1/PFC_CFG0=
PFC1(0/1).
IWAKE/RSNS1/RSNS0=Thesebitsconfigurethecurrentwakefunction(seeTable11).Defaultis0/0/1.
IDSELEN=Enablescellprofileselectionfeature.Truewhenset.Defaultis1.
SLEEP=Thefuelgaugecanentersleep,ifoperatingconditionsallow.Truewhenset.Defaultis1.
RMFCC=RMisupdatedwiththevaluefromFCC,onvalidchargetermination.Truewhenset.Defaultis1
BATL_POL=BAT_LOWpinisactive-high.Truewhenset.Defaultis1.
BATG_POL=BAT_LOW/BAT_GDpinisactive-low.Truewhencleared.Defaultis0.
BAT_FN=SelectsBAT_LOW(bitclear)or/BAT_GD(bitset)functiononpin12.Defaultis0.
TEMPS=SelectsexternalthermistorforTemperature()measurements.Truewhenset.Defaultis1.
Thebq27510hasthreepossiblepin-functionvariationsthatcanbeselectedinaccordancewiththecircuit
architectureoftheendapplication.Eachvariationhasbeenassignedapinfunctioncode,orPFC.
WhenthePFCissetto0,onlythebq27510measuresbatterytemperatureunderdischargeandrelaxation
conditions.Thechargerdoesnotreceiveanyinformationfromthebq27510aboutthetemperaturereadings,and
thereforeoperatesopen-loopwithrespecttobatterytemperature.
APFCof1islikeaPFCof0,excepttemperatureisalsomonitoredduringbatterycharging.Ifcharging
temperaturefallsoutsideofthepresetrangedefinedindataflash,achargercanbedisabledviathe
BAT_LOW/BAT_GDpin,untilcelltemperaturerecovers.SeeSectionChargeInhibitforadditionaldetails.
FinallywhenthePFCissetto2,thebatterythermistorcanbesharedbetweenthefuelgaugeandthecharger.
Thechargerhasfullusageofthethermistorduringbatterycharging,whilethefuelgaugeusesthethermistor
exclusivelyduringdischargeandbatteryrelaxation.
ThePFCisspecifiedinOperationConfiguration[PFC_CFG1,PFC_CFG0].ThedefaultisPFC=1.
TheBAT_LOW/BAT_GDisamultiplexpin.Thefunctionisdefinedby[BAT_FN]asasystemprocessorwithan
electricalindicatorofbatterystatus.IttheBAT_LOWfunctionisactivated,thesignalingonthemultiplexedpin
followsthestatusofthe[SOC1]bitintheFlags()register.Notethatthepolarityofthepinoutputcanbeinverted
viathe[BATL_POL]bitoftheOperationConfiguration.
Thebq27510mustoperateinconjunctionwithotherelectronicsinasystemappliance,suchaschargersorother
ICsandapplicationcircuitsthatdrawappreciablepower.Afterabatteryisinsertedintothesystem,thereshould
benochargingordischargingcurrenthigherthanC/20,sothatanaccurateOCVcanberead.TheOCVisused
forhelpingdeterminewhichbatteryprofiletouse,asitconstitutespartofthebatteryimpedancemeasurement.
Whenabatteryisinsertedintoasystem,theImpedanceTrack™algorithmrequiresthatnochargingofthe
batterytakesplaceandthatanydischargeislimitedtolessthanC/20–theseconditionsaresufficientforthefuel
gaugetotakeanaccurateOCVreading.Todisablethesefunctions,theBAT_LOW/BAT_GDpinismerely
negatedfromthedefaultsetting.OnceanOCVreadinghasbemade,theBAT_LOW/BAT_GDpinisasserted,
therebyenablingbatterychargingandregulardischargeofthebattery.TheOperationConfiguration
[BATG_POL]bitcanbeusedtosetthepolarityofthebatterygoodsignal,shouldthedefaultconfigurationneed
tobechanged.
InPFC1,theBAT_LOW/BAT_GDpinisalsousedtodisablebatterychargingwhenthebq27510readsbattery
temperaturesoutsidetherangedefinedby[ChargeInhibitTempLow,ChargeInhibitTempHigh].The
BAT_LOW/BAT_GDlineisreturnedtodesertedstateoncetemperaturefallswithintherange[ChargeInhibit
TempLow+TempHys,ChargeInhibitTempHigh–TempHys].
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