Datasheet

FlashUpdates
AUTOCALIBRATION
APPLICATION-SPECIFICINFORMATION
BATTERYPROFILESTORAGEANDSELECTION
CommonProfileAspects
bq27510-G1
www.ti.com .....................................................................................................................................................................................................SLUS927–APRIL2009
Table11.I
WAKE
ThresholdSettings
(1)
RSNS1RSNS0IWAKEVth(SRP-SRN)
000Disabled
001Disabled
010+1.0mVor–1.0mV
011+2.2mVor–2.2mV
100+2.2mVor–2.2mV
101+4.6mVor–4.6mV
110+4.6mVor–4.6mV
111+9.8mVor–9.8mV
(1)Theactualresistancevalueversusthesettingofthesenseresistorisnotimportant;justtheactual
voltagethresholdwhencalculatingtheconfiguration.Thevoltagethresholdsaretypicalvaluesunder
roomtemperature.
DataFlashcanonlybeupdatedifVoltage()≥FlashUpdateOKVoltage.Flashprogrammingcurrentcancause
anincreaseinLDOdropout.ThevalueofFlashUpdateOKVoltageshouldbeselectedsuchthatthebq27510
Vccvoltagedoesnotfallbelowitsminimumof2.4VduringFlashwriteoperations.
Thebq27510providesanautocalibrationfeaturethatwillmeasurethevoltageoffseterroracrossSRPandSRN
fromtime-to-timeasoperatingconditionschange.Itsubtractstheresultingoffseterrorfromnormalsense
resistorvoltage,VSR,formaximummeasurementaccuracy.
AutocalibrationoftheADCbeginsonentrytoSLEEPmode,exceptifTemperature()is≤5°CorTemperature()
=45°C.
Thefuelgaugealsoperformsasingleoffsetwhen(1)theconditionofAverageCurrent()≤100mAand(2)
{voltagechangesincelastoffsetcalibration≥256mV}or{temperaturechangesincelastoffsetcalibrationis
greaterthan80°Cfor≥60s}.
Capacityandcurrentmeasurementswillcontinueatthelastmeasuredrateduringtheoffsetcalibrationwhen
thesemeasurementscannotbeperformed.Ifthebatteryvoltagedropsmorethan32mVduringtheoffset
calibration,theloadcurrenthaslikelyincreasedconsiderably;hence,theoffsetcalibrationwillbeaborted.
Whenabatterypackisremovedfromsystemequipmentthatimplementsthebq27510,thefuelgaugemaintains
someofthebatteryinformation,incaseitisre-inserted.ThiswaytheImpedanceTrack™algorithmoftenhasa
meansofrecoveringbattery-statusinformation,therebymaintaininggoodstate-of-charge(SOC)estimates.
Thedefaultbatteryprofilesareavailabletostorebatteryinformation.TheyareusedtoprovidetheImpedance
Track™algorithmwiththedefaultinformationonthebatterytypeexpectedtobeusedwiththeend-equipment.
Thedefaultprofilescanbeusedtosupportbatteriesofsamechemistrybutdifferentcapacities.Defaultprofiles
areprogrammedbytheend-equipmentmanufacturer.Onlyoneofthedefaultprofilescanbeselected,andthis
selectioncannotbechangedduringend-equipmentoperation.
Inadditiontothedefaultprofiles,thebq27510maintainstwoactiveprofiles:Cell0andCell1.Thesetableshold
dynamicbatterydata,andkeeptrackofthestatusforuptotwoofthemostrecentbatteriesused.Inmostcases
thebq27510canadministrateinformationontworemovablebatterypacks.
Copyright©2009,TexasInstrumentsIncorporatedSubmitDocumentationFeedback29
ProductFolderLink(s):bq27510-G1
Not Recommended For New Designs