Datasheet

BATINSERTCHECKMode
HIBERNATEMode
POWERCONTROL
ResetFunctions
bq27510-G1
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Thebq27510exitsSLEEPifanyentryconditionisbroken,specificallywhen(1)AverageCurrent()risesabove
SleepCurrent,or(2)acurrentinexcessofI
WAKE
throughR
SENSE
isdetected.
Intheeventthatabatteryisremovedfromthesystemwhileachargerispresent(andpoweringthegauge),
ImpedanceTrack™updatesarenotnecessary.Hence,thefuelgaugeentersastatethatchecksforbattery
insertionanddoesnotcontinueexecutingtheImpedanceTrack™algorithm.
Thismodeisahalted-CPUstatethatoccurswhenanadapter,orotherpowersource,ispresenttopowerthe
bq27510(andsystem),yetnobatteryhasbeendetected.Whenbatteryinsertionisdetected,aseriesof
initializationactivitiesbegin,whichinclude:OCVmeasurement,settingtheBAT_GDpin,andselectingthe
appropriatebatteryprofiles.Thebatteryinsertiondetectiontakesabout3ms.
Somecommands,issuedbyasystemprocessor,canbeprocessedwhilethebq27510ishaltedinthismode.
Thegaugewillwakeuptoprocessthecommand,thenreturntothehaltedstateawaitingbatteryinsertion.
HIBERNATEmodeshouldbeusedwhenthesystemequipmentneedstoenteraverylow-powerstate,and
minimalgaugepowerconsumptionisrequired.Thismodeisidealwhenasystemequipmentissettoitsown
HIBERNATE,SHUTDOWN,orOFFmodes.ThefuelgaugecanenterHIBERNATEduetoeitherlowcellvoltage
orlowloadcurrent.
•HIBERNATEduetothecellvoltage.WhenthecellvoltagedropsbelowtheHibernateVoltageandavalid
OCVmeasurementhasbeentaken,thefuelgaugeentersHIBERNATEmodeThe[HIBERNATE]bitofthe
CONTROLregisterhasnoimpactforthefuelgaugetoentertheHIBERNATEmode.
•HIBERNATEduetotheloadcurrent.IfthefuelgaugeenterstheHIBERNATEmodeduetotheloadcurrent,
the[HIBERNATE]bitoftheCONTROL_STATUSregistermustbeset.ThegaugewaitstoenterHIBERNATE
modeuntilithastakenavalidOCVmeasurementandthemagnitudeoftheaveragecellcurrenthasfallen
belowHibernateCurrent.
ThegaugewillremaininHIBERNATEmodeuntilthesystemissuesadirectI2Ccommandtothegaugeora
PORoccurs.I2CCommunicationthatisnotdirectedtothegaugewillnotwakethegauge(oratleastforvery
long).
DuringHibernatemodethe/BAT_GDsignalisnegated(nobatterycharging/discharging).Thispreventsa
chargerapplicationfrominadvertentlychargingthebatterybeforeanOCVreadingcanbetaken.Itisthe
system’sresponsibilitytowakethebq27510afterithasgoneintoHIBERNATEmode.Afterwaking,thegauge
canproceedwiththeinitializationofthebatteryinformation(OCV,profileselection,etc.)
ItissuggestedtokeepthesystemintheSLEEPmodeinsteadofHIBERNATEmodewhenachargeris
attached.ThereasonisthatchargerremovalwillnotwakeupthebatteryfromHIBERNATEmode.
Whenthebq27510detectsasoftwarereset([RESET]bitofControl()initiated),itdeterminesthetypeofreset
andincrementsthecorrespondingcounter.ThisinformationisaccessiblebyissuingthecommandControl()
functionwiththeRESET_DATAsubcommand.
AsshowninFigure3ifapartialresetwasdetected,aRAMchecksumisgeneratedandcomparedagainstthe
previouslystoredchecksum.Ifthechecksumvaluesdonotmatch,theRAMisreinitialized(aFullReset).The
storedchecksumisupdatedeverytimeRAMisaltered.
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