nand_design_guide

TOSHIBAAMERICAELECTRONICCOMPONENTS,INC.NANDFlashApplicationsDesignGuideSystemSolutionsfromToshibaAmericaElectronicComponents,Inc.AtsushiInoue,StaffMTS,MemoryBusinessUnitDougWong,StaffMTS,MemoryBusinessUnitRevision2.0March2004TOSHIBAAMERICAELECTRONICCOMPONENTS,INC.3TOSHIBAAMERICAELECTRONICCOMPONENTS,INC.Copyright©2004byToshibaAmericaElectronicComponents,Inc.AllRightsReserved.ThisNANDFlashApplicationsDesignGuideandtheinformationandknow-howitcontainsconstitutetheexclu-sivepropertyofToshibaAmericaElectronicComponents,Inc.(“TAEC”),andmaynotbereproducedordisclosedtootherswithouttheexpresspriorwrittenpermissionofTAEC.Anypermittedreproductions,inwholeorinpart,shallbearthisnotice.TheinformationinthisNANDFlashApplicationsDesignGuidehasbeenchecked,andisbelievedtobereliable;however,thereaderunderstandsandagreesthatTAECMAKESNOWARRANTYWITHRESPECTTOTHISDESIGNGUIDE,ITSCONTENTSORTHEIRACCURACY,ANDEXCLUDESALLEXPRESSANDIMPLIEDWARRANTIES,INCLUDINGWARRANTIESOFFITNESSFORAPARTICULARPURPOSE,MERCHANTABILI-TY,ORNON-INFRINGEMENT.Thereaderfurtherunderstandsthatheorsheissolelyresponsibleforalluseoftheinformationcontainedwithin,including,butnotlimitedto,securinganynecessaryintellectualpropertyrights,howeverdenominated.AllinformationinthisNANDFlashApplicationsDesignGuideissubjecttochangewithoutpriornotice,atTAEC’ssolediscretion.Alltrademarks,tradenames,product,and/orbrandnamesarethepropertyoftheirrespectiveholders.*Theinformationcontainedhereinissubjecttochangewithoutnotice.*Theinformationcontainedhereinispresentedonlyasaguidefortheapplicationsofourproducts.NoresponsibilityisassumedbyTOSHIBAforanyinfringementsofpatentsorotherrightsofthethirdpartieswhichmayresultfromitsuse.NolicenseisgrantedbyimplicationorotherwiseunderanypatentorpatentrightsofTOSHIBAorothers.*TOSHIBAiscontinuallyworkingtoimprovethequalityandreliabilityofitsproducts.Nevertheless,semiconductordevicesingeneralcanmalfunctionorfailduetotheirinherentelectricalsensitivityandvulnerabilitytophysicalstress.Itistheresponsibilityofthebuyer,whenutilizingTOSHIBAproducts,tocomplywiththestandardsofsafetyinmakingasafedesignfortheentiresystem,andtoavoidsituationsinwhichamalfunctionorfailureofsuchTOSHIBAproductscouldcauselossofhumanlife,bodilyinjuryordamagetoproperty.Indevelopingyourdesigns,pleaseensurethatTOSHIBAproductsareusedwithinspecifiedoperatingrangesassetforthinthemostrecentTOSHIBAproductsspecifications.Also,pleasekeepinmindtheprecautionsandconditionssetforthinthe“HandlingGuideforSemiconductorDevices,”or“TOSHIBASemiconductorReliabilityHandbook,”etc.*TheToshibaproductslistedinthisdocumentareintendedforusageingeneralelectronicsapplications(computer,personalequipment,officeequipment,measuringequipment,industrialrobotics,domesticappliances,etc.).TheseToshibaproductsareneitherintendednorwarrantedforusageinequipmentthatrequiresextraordinarilyhighqualityand/orreliabilityoramalfunctionorfailureofwhichmaycauselossofhumanlifeorbodilyinjury(“UnintendedUsage”).UnintendedUsageincludeatomicenergycontrolinstruments,airplaneorspaceshipinstruments,transportationinstruments,trafficsignalinstruments,combustioncontrolinstruments,medicalinstruments,alltypesofsafetydevices,etc.UnintendedUsageofToshibaproductslistedinthisdocumentshallbemadeatthecustomer’sownrisk.*Theproductsdescribedinthisdocumentmayincludeproductssubjecttoforeignexchangeandforeigntradelaws.*TheproductscontainedhereinmayalsobecontrolledundertheU.S.ExportAdministrationRegulationsand/orsubjecttotheapprovaloftheU.S.DepartmentofCommerceorU.S.DepartmentofStatepriortoexport.Anyexportorre-export,directlyorindirectlyincontraventionofanyoftheapplicableexportlawsandregulations,isherebyprohibited.(INITIALBADBLOCKS)...............................186.2BLOCKSTHATFAILDURINGUSE...............................................196.3FAILUREMODESMECHANISMANDSYMPTOMS...................................19PermanentFailures..........................................................19SoftErrors.................................................................197.MANAGINGNANDFLASH........................................................237.1BADBLOCKMANAGEMENT..........................................