Problem with NAND memory data retention

[Lukasz Majewski]

Dear All,

I'd like to ask you for sharing your experience with NAND Flash devices
- which may be older that their data retention time.

I've a problem with Flash NAND memory (Samsung 128Mx8).

In the data sheet [1] the manufacturer claims that it has 10 years for
data retention. The device equipped with it is a bit older than 10
years.


How one can diagnose that data retention time for NAND Flash has been
exceeded?

Is that:

- The number of bit flip errors on a RW page so large that ECC cannot
  fix it?

- Or are whole RW pages erased (0xFF)/corrupted/cleared (0x00)?

- Or any other evidence?


Thanks in advance for your help.


[1] -
http://www.sst-ic.com/File/Seriea/PDF/100923163334f47b2ce6-13b7-43d0-9b8c-ec1c75ca2c6f.pdf


Best regards,

Lukasz Majewski

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