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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

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