NAND02G-B2D NUMONYX [Numonyx B.V], NAND02G-B2D Datasheet - Page 45

• Manufacturer Part Number: NAND02G-B2D
• Description: 2-Gbit, 2112-byte/1056-word page multiplane architecture, 1.8 V or 3 V, NAND flash memories
• Manufacturer: NUMONYX [Numonyx B.V]

NAND02G-B2D
8.2
NAND flash memory failure modes
Over the lifetime of the device bad blocks may develop. To implement a highly reliable
system, the possible failure modes must be considered.
Refer to
during an operation.
Table 20.
Figure 20. Bad block management flowchart
Program/erase failure
In this case, the block has to be replaced by copying the data to a valid block. These
additional bad blocks can be identified because attempts to program or erase them
gives errors in the Status register. As the failure of a page program operation does not
affect the data in other pages in the same block, the block can be replaced by
reprogramming the current data and copying the rest of the replaced block to an
available valid block. The Copy Back Program command copies the data to a valid
block. See
Read failure
In this case, ECC correction must be implemented. To efficiently use the memory
space, the recovery of a single-bit error in read by ECC, without replacing the whole
block, is recommended.
Table 20: Block failure
Operation
Program
Block failure
Erase
Read
Section 6.5: Copy back program
Block Address =
for the recommended procedure to follow if an error occurs
START
Block 0
= FFh?
block?
Data
Last
END
YES
YES
NO
NO
Bad Block table
for more details.
Update
Block Address
Increment
Block replacement
Block replacement
Procedure
ECC
AI07588C
Software algorithms
45/69