2 invalid block replacement operation – Samsung MUXONENAND A-DIE KFM2G16Q2A User Manual
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MuxOneNAND2G(KFM2G16Q2A-DEBx)
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FLASH MEMORY
MuxOneNAND4G(KFN4G16Q2A-DEBx)
Invalid Block Table Creation Flow Chart
3.18.2 Invalid Block Replacement Operation
Within its life time, additional invalid blocks may develop with NAND Flash Array memory. Refer to the device's qualification report for the
actual data.
The following possible failure modes should be considered to implement a highly reliable system.
In the case of a status read failure after erase or program, a block replacement should be done. Because program status failure during a page
program does not affect the data of the other pages in the same block, a block replacement can be executed with a page-sized buffer by find-
ing an erased empty block and reprogramming the current target data and copying the rest of the replaced block.
Block Failure Modes and Countermeasures
Failure Mode
Detection and Countermeasure sequence
Erase Failure
Status Read after Erase --> Block Replacement
Program Failure
Status Read after Program --> Block Replacement
Single Bit Failure in Load Operation
Error Correction by ECC mode of the device
*
Start
Set Block Address = 0
Check
Increment Block Address
Last Block ?
End
No
Yes
Yes
Create (or update)
No
Invalid Block(s) Table
"FFFFh" ?
Check "FFFFh" at the 1st word of sector 0
of spare area in 1st and 2nd page