TC58NVG1S3ETAI0
2012-09-01C
60
(13) Invalid blocks (bad blocks)
The device occasionally contains unusable blocks. Therefore, the following issues must be recognized:
Please do not perform an erase operation to bad blocks. It may be
impossible to recover the bad block information if the information is
erased.
Check if the device has any bad blocks after installation into the system.
Refer to the test flow for bad block detection. Bad blocks which are
detected by the test flow must be managed as unusable blocks by the
system.
A bad block does not affect the performance of good blocks because it is
isolated from the bit lines by select gates.
The number of valid blocks over the device lifetime is as follows:
MIN TYP. MAX UNIT
Valid (Good) Block Number 2008 ⎯ 2048 Block
Bad Block Test Flow
Regarding invalid blocks, bad block mark is in either the 1st or the 2nd page.
*1: No erase operation is allowed to detected bad blocks
Bad Block
Bad Block
Pass
Read Check
Start
Bad Block *1
Last Block
End
Yes
Fail
Block No = 1
No
Block No. = Block No. + 1
Read Check :
Read either column 0 or 2048 of the 1st page or the
2nd page of each block. If the data of the column is not
FF (Hex), define the block as a bad block.
