Single Cell Li-Ion Battery Fuel Gauge for Battery Pack ...

1 Battery PackPACK PROTECTIONICPACK+ DECEMBER2008 SingleCellLi-IonBatteryFuelGaugeforBatte ryPackIntegrationCheckforSamples:bq27541 1 FEATURESAPPLICATIONS Smartphones23 BatteryFuelGaugefor1-SeriesLi-IonApplica tions PDAs DigitalStillandVideoCameras MicrocontrollerPeripheralProvides: HandheldTerminals AccurateBatteryFuelGauging MP3orMultimediaPlayers InternalTemperatureSensorforSystemTemper atureReportingDESCRIPTION SHA-1/HMACA uthenticationTheTexasInstrumentsbq27541L i-Ionbatteryfuel BatteryFuelGaugingBasedonPatenteddevicer equireslittlesystemmicrocontrollerfirmwa reImpedanceTrack ModelsBatteryDischargeCurveforsystem smain-boardwithanembeddedbatteryAccurate Time-To-EmptyPredictions(nonremovable). AutomaticallyAdjustsforBatteryAging,Batt erySelf-Discharge,andThebq27541usesthepa tentedImpedanceTrack algorithmforfuelgauging,andprovidesinfor mationTemperature/RateInefficienciessuch asremainingbatterycapacity(mAh), Low-ValueSenseResistor(5m to20m )state-of-charge(%),run-timetoempty(min. )

2 , Battery HDQandI2C InterfaceFormatsforvoltage(mV),andtemper ature( C).CommunicationwithHostSystemThebq27541 alsofeaturesintegratedsupportfor Small12-pin2,5mm 4 mmSONP ackagesecurebatterypackauthentication,us ingtheSHA-1 ,standardwarranty,andusein a is a 2008, ,2,5-mm 4-mmSON 40 C to85 CI2C,HDQ(1)bq27541 DRZT250(1)bq27541is shippedin I2 Cmodebq27541(TOPVIEW) (1) serialcommunicationsclockinputlineforcom municationwithsystem(Slave).Usewith10k pull-upresistor(typical).SDA10I/OSlaveI2 C serialcommunicationsdatalineforcommunica tionwithsystem(Slave).Open- pull-upresistor(typical). (Slave). to20-m to20-m senseresistorTS9 IAPackthermistorvoltagesense(use103AT-ty pethermistor). (1)I/O= Digitalinput/output,IA= Analoginput,P = Powerconnection2 SubmitDocumentationFeedbackCopyright 2008,TexasInstrumentsIncorporatedProduct FolderLink(s) DECEMBER2008 ELECTRICALSPECIFICATIONSABSOLUTEMAXIMUMR ATINGS overoperatingfree-airtemperaturerange(un lessotherwisenoted)(1)VALUEUNITVIR egulatorinput,REGIN (SDA,SCL,HDQ) ,(pin4) (pins1,7,8,9) + (HBM), (HBM),allpins2 TFFunctionaltemperaturerange 40to100 CTstgStoragetemperaturerange 65to150 C(1) ,andfunctionaloperationofthedeviceatthes eoranyotherconditionsbeyondthoseindicate dunderrecommendedoperatingconditionsis 40 CDERATINGFACTORPACKAGE(1)RqJAPOWERRATING TA 40 C12-pinDRZ(2) C176 C/W(1)

3 Forthemostcurrentpackageandorderinginfor mation,seethePackageOptionAddendumatthee ndofthisdocument, (2)Thisdatais basedonusinga 4-layerJEDEC high-Kboardwiththeexposeddiepadconnected toa connectedtothegroundplanebya 2- -40 C to85 C;typicalvaluesatTA= 25 C andV(REGIN)= VBAT= (unlessotherwisenoted) , >ICCN ormaloperatingmodecurrent(1)131mASleepCu rrentFuelgaugein (SLP)Low-poweroperatingmodecurrent(1)60m AILOAD<SleepCurrentFuelgaugein (FULLSLP)Low-poweroperatingmodecurrent(1 )21mAILOAD<SleepCurrentFuelgaugein (HIB)Hibernateoperatingmodecurrent(1)6mA ILOAD<HibernateCurrentOutputvoltagelow(H DQ,SDA,SCL,VOLIOL= 3 )VOH(PP)Outputhighvoltage(SE)IOH= -1mAVCC (OD)Outputhighvoltage(HDQ,SDA,SCL)Extern alpull-upresistorconnectedtoVccVCC (HDQ,SDA,SCL) (HDQ,SDA,SCL) (A1)Inputvoltagerange(TS)VSS (A2)Inputvoltagerange(BAT)VSS (A3)Inputvoltagerange(SRP,SRN)VSS (I/Opins) (1) 2008,TexasInstrumentsIncorporatedSubmitD ocumentationFeedback3 ProductFolderLink(s).

4 Bq27541 NotRecommendedforNewDesignsbq27541 SLUS861 40 C to85 C,C(REG)= , < V(REGIN)= VBAT< ;typicalvaluesatTA= 25 C andV(REGIN)= VBAT= (unlessotherwisenoted)PARAMETERTESTCONDI TIONSMINTYPMAXUNITVIT+ LDOREGULATOR(1)TA= 40 C to85 C,C(REG)= , < V(REGIN)= VBAT< ;typicalvaluesatTA= 25 C andV(REGIN)= VBAT= (unlessotherwisenoted) V(REGIN) ,TA= 40 C to85 16mARegulatoroutputvoltage, V(REGIN)< (lowTA= 40 C to85 ),IOUT ,IOUT 16mA280 VDOR egulatordropoutvoltageTA= 40 C to85 ,IOUT 3 mA50V(REGIN)= ,Regulatoroutputchange V(REGTEMP)TA= 40 C to85 16mA V(REGLINE) V(REGIN) ,IOUT= IOUT 3 mA,V(REGIN)= V(REGLOAD)LoadregulationmV3 mA IOUT 16mA,V(REGIN)= (2)ShortcircuitcurrentlimitV(REG25)= 0 V,TA= 40 C to85 C250mA(1)LDOoutputcurrent,IOUT, is thesumofinternalandexternalloadcurrents.

5 (2) 40 C to85 C,C(REG)= , < V(REGIN)= VBAT< ;typicalvaluesatTA= 25 C andV(REGIN)= VBAT= (unlessotherwisenoted)PARAMETERTESTCONDI TIONSMINTYPMAXUNITG(TEMP)Temperaturesens orvoltagegain 2mV/ CHIGHFREQUENCYOSCILLATORTA= 40 C to85 C,C(REG)= , < V(REGIN)= VBAT< ;typicalvaluesatTA= 25 C andV(REGIN)= VBAT= (unlessotherwisenoted) 0 C to60 C (1)(2)TA= 20 C to70 C 40 C to85 (3) (1)Thefrequencyerroris (2)Thefrequencydriftis includedandmeasuredfromthetrimmedfrequen cyatVCC= ,TA= 25 C.(3)Thestartuptimeis definedasthetimeit takesfortheoscillatoroutputfrequencytobe 3% 2008,TexasInstrumentsIncorporatedProduct FolderLink(s) DECEMBER2008 LOWFREQUENCYOSCILLATORTA= 40 C to85 C,C(REG)= , < V(REGIN)= VBAT< ;typicalvaluesatTA= 25 C andV(REGIN)= VBAT= (unlessotherwisenoted) 0 C to60 C (1)(2)TA= 20 C to70 C 40 C to85 (3)500ms(1)Thefrequencydriftis includedandmeasuredfromthetrimmedfrequen cyatVCC= ,TA= 25 C.

6 (2)Thefrequencyerroris (3)Thestartuptimeis definedasthetimeit takesfortheoscillatoroutputfrequencytobe 3% (COULOMBCOUNTER)CHARACTERISTICSTA= 40 C to85 C,C(REG)= , < V(REGIN)= VBAT< ;typicalvaluesatTA= 25 C andV(REGIN)= VBAT= (unlessotherwisenoted)PARAMETERTESTCONDI TIONSMINTYPMAXUNITVIN(SR)Inputvoltageran ge,V(SRN)andV(SRP)VSR= V(SRN) V(SRP) (SR)ConversiontimeSingleconversion1sReso lution1415bitsVOS(SR)Inputoffset10mVINLI ntegralnonlinearityerror (SR)Effectiveinputresistance(1) Ilkg(SR)Inputleakagecurrent(1) (1) (TEMPERATUREANDCELLMEASUREMENT)CHARACTER ISTICSTA= 40 C to85 C,C(REG)= , < V(REGIN)= VBAT< ;typicalvaluesatTA= 25 C andV(REGIN)= VBAT= (unlessotherwisenoted)PARAMETERTESTCONDI TIONSMINTYPMAXUNITVIN(ADC)Inputvoltagera nge (ADC)Conversiontime125msResolution1415bi tsVOS(ADC)Inputoffset1mVZ(ADC1)Effective inputresistance(TS)(1)8M Z(ADC2)Effectiveinputresistance(BAT)(1)b q27541notmeasuringcellvoltage8M bq27541measuringcellvoltage100k Ilkg(ADC)Inputleakagecurrent(1) (1) 40 C to85 C,C(REG)= , < V(REGIN)= VBAT<.

7 TypicalvaluesatTA= 25 C andV(REGIN)= VBAT= (unlessotherwisenoted)PARAMETERTESTCONDI TIONSMINTYPMAXUNITtDRDataretention(1)10 YearsFlashprogrammingwrite-cycles(1)20,0 00 CyclestWORDPROGW ordprogrammingtime(1)2msICCPROGF lash-writesupplycurrent(1)510mA(1) 2008,TexasInstrumentsIncorporatedSubmitD ocumentationFeedback5 ProductFolderLink(s):bq27541t(B)t(BR)(a) Break and Break Recovery(b) Host Transmitted Bitt(HW1)t(HW0)t(CYCD)Break7 - Bit Address1-BitR/W8 - Bit Datat(RSPS)(c) Gauge Transmit Bitt(DW1)t(DW0)(d) Gauge to Host Responset(CYCH)NotRecommendedforNewDesig nsbq27541 SLUS861 40 C to85 C,CREG= , < VREGIN= VBAT< ;typicalvaluesatTA= 25 C andVREGIN= VBAT= (unlessotherwisenoted)PARAMETERTESTCONDI TIONSMINTYPMAXUNITt(CYCH)Cycletime,hostt obq27541190mst(CYCD)Cycletime,bq27541toh ost190205250mst(HW1)Hostsends1 (DW1)bq27541sends1 tohost3250mst(HW0)Hostsends0 tobq2754186145mst(DW0)bq27541sends0 tohost80145mst(RSPS)Responsetime,bq27541 tohost190320mst(B)Breaktime190mst(BR) (a),HDQH osttobq27541communication(b),bq27541toHo stcommunication(c),andbq27541toHostrespo nseformat(d).

8 6 SubmitDocumentationFeedbackCopyright 2008,TexasInstrumentsIncorporatedProduct FolderLink(s):bq27541tSU(STA)SCLSDAtw(H) tw(L)tftrt(BUF)trtd(STA)REPEATEDSTARTth( DAT)tsu(DAT)tftsu(STOP) DECEMBER2008I2C-COMPATIBLEINTERFACECOMMU NICATIONTIMINGCHARACTERISTICSTA= 40 C to85 C,CREG= , < VREGIN= VBAT< ;typicalvaluesatTA= 25 C andVREGIN= VBAT= (unlessotherwisenoted)PARAMETERTESTCONDI TIONSMINTYPMAXUNITtrSCL/SDArisetime300ns tfSCL/SDAfalltime300nstw(H)SCLpulsewidth (high)600nstw(L)SCLpulsewidth(low) (STA)Setupforrepeatedstart600nstd(STA)St arttofirstfallingedgeofSCL600nstsu(DAT)D atasetuptime1000nsth(DAT)Dataholdtime0ns tsu(STOP) 2008,TexasInstrumentsIncorporatedSubmitD ocumentationFeedback7 ProductFolderLink(s):bq27541 NotRecommendedforNewDesignsbq27541 SLUS861 ,suchasstate-of-charge(SOC),time-to-empt y(TTE)andtime-to-full(TTF).

9 Informationisaccessedthrougha seriesofcommands,calledStandardCommands. ,indicatedbythegeneralformatCommand(), areusedtoreadandwriteinformationcontaine dwithinthebq27541controlandstatusregiste rs, s serialcommunicationsengine,andcanbeexecu tedduringapplicationdevelopment,packmanu facture, ,generally, achievedbyeitheruseofthebq27541 s companionevaluationsoftware,throughindiv idualcommands,orthrougha desireddataflashlocation, ,partitionedinto3 32-byteblocks:ManufacturerInfoBlockA,Man ufacturerInfoBlockB, andManufacturerInfoBlockC. Thisdataspaceisaccessedthrougha ,seesectionManufacturerInformationBlocks . Thekeytothebq27541 s high-accuracygasgaugingpredictionisTexas Instrument sproprietaryImpedanceTrack ,characteristics,andpropertiestocreatest ate-of-chargepredictionsthatcanachievele ssthan1%erroracrossa small-valueseriessenseresistor(5m to20m typ.)

10 LocatedbetweentheCELL-andthebattery s cellisattachedtothebq27541,cellimpedance is computed,basedoncellcurrent,cellopen-cir cuitvoltage(OCV), highaccuracynegativetemperaturecoefficie nt(NTC)thermistorwithR25= 10K 1%andB25/85= 3435K 1%(suchasSemitec103 ATformeasurement). , ,thebq27541hasdifferentpowermodes:NORMAL ,SLEEP,FULLSLEEP,HIBERNATE, ,dependingupontheoccurrenceofspecificeve nts,thougha :Commands:italicswithparentheses() ()DataFlash:italics,bold, :italicswithbrackets[]. [TDA]Dataflashbits:italics,bold, andbrackets[]. :[LED1] 2008,TexasInstrumentsIncorporatedProduct FolderLink(s) DECEMBER2008 STANDARDDATACOMMANDST hebq27541usesa ,asindicatedinTable1. Becauseeachcommandconsistsoftwobytesofda ta,twoconsecutiveI2 Ctransmissionsmustbeexecutedbothtoinitia tethecommandfunction, ,suchasspooling, ()CNTL0x00/ 0x01N/AR/WAtRate()AR0x02/ 0x03mAR/WAtRateTimeToEmpty()ARTTE0x04/ 0x05 MinutesRTemperature()TEMP0x06/ ()VOLT0x08/ 0x09mVRFlags()FLAGS0x0a/ 0x0bN/ARNominalAvailableCapacity()NAC0x0 c/ 0x0dmAhRFullAvailableCapacity()FAC0x0e/ 0x0fmAhRRemainingCapacity()RM0x10/ 0x11mAhRFullChargeCapacity()FCC0x12/ 0x13mAhRAverageCurrent()AI0x14/ 0x15mARTimeToEmpty()TTE0x16/ 0x17 MinutesRTimeToFull()TTF0x18/ 0x19 MinutesRStandbyCurrent()SI0x1a/ 0x1bmARStandbyTimeToEmpty()STTE0x1c/ 0x1dMinutesRMaxLoadCurrent()MLI0x1e/ 0x1fmARMaxLoadTimeToEmpty()MLTTE0x20/ 0x21 MinutesRAvailableEnergy()