tc58dvm92a5tai0 TOSHIBA Semiconductor CORPORATION, tc58dvm92a5tai0 Datasheet - Page 33

• Manufacturer Part Number: tc58dvm92a5tai0
• Description: 512-mbit 64m ? 8 Bits Cmos Nand E Prom Description
• Manufacturer: TOSHIBA Semiconductor CORPORATION

(14)
Bad Block Test Flow
Invalid blocks (bad blocks)
and do not use these bad blocks.
The device contains unusable blocks. Therefore, at the time of use, please check whether a block is bad
Figure 24
Block No. = Block No. + 1
* 1: No erase operation is allowed to detected bad blocks
Bad Block
Bad Block
No
Block, all bytes are not in the FFh state. Please don’t perform erase
operation to Bad Block.
Figure 25 shows 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.
isolated from the Bit line by the Select gate
Valid (Good) Block Number
At the time of shipment, all data bytes in a Valid Block are FFh. For Bad
Check if the device has any bad blocks after installation into the system.
A bad block does not affect the performance of good blocks because it is
The number of valid blocks over the device lifetime is as follows:
Block No. = 4096
Block No = 1
Read Check
Figure 25
Start
End
Pass
Yes
33
Fail
4016
MIN
Read Check: Read column 517 of the 1st page
Bad Block * 1
TYP.
⎯
in the block. If the column is not
FFh , define the block as a bad
block.
TC58DVM92A5TAI0
MAX
4096
2010-04-23
UNIT
Block