Datasheet

SEALING/UNSEALINGDATAFLASH
bq27510-G1
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AlthoughFULLACCESSandUNSEALEDmodesappearidentical,onlyFULLACCESSmodeallowsthe
bq27510towriteaccess-modetransitionkeys.
Thebq27510implementsakey-accessschemetotransitionbetweenSEALED,UNSEALED,and
FULL-ACCESSmodes.Eachtransitionrequiresthatauniquesetoftwokeysbesenttothebq27510viathe
Control()controlcommand.Thekeysmustbesentconsecutively,withnootherdatabeingwrittentothe
Control()registerinbetween.Notethattoavoidconflict,thekeysmustbedifferentfromthecodespresentedin
theCNTLDATAcolumnofTable2subcommands.
WheninSEALEDmodethe[SS]bitofCONTROL_STATUSisset,butwhentheUNSEALkeysarecorrectly
receivedbythebq27510,the[SS]bitiscleared.Whenthefull-accesskeysarecorrectlyreceivedthenthe
CONTROL_STATUS[FAS]bitiscleared.
Boththesetsofkeysforeachlevelare2byteseachinlengthandarestoredindataflash.TheUNSEALkey
(storedatUnsealKey0andUnsealKey1)andtheFULL-ACCESSkey(storedatFullAccessKey0andFull
AccessKey1)canonlybeupdatedwheninFULL-ACCESSmode.Theorderofthebytesenteredthroughthe
Control()commandisthereverseofwhatisreadfromthepart.Forexample,ifthe1stand2ndwordofthe
UnSealKey0returns0x1234and0x5678,thenControl()shouldsupply0x3412and0x7856tounsealthepart.
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