k9f6408u0a Samsung Semiconductor, Inc., k9f6408u0a Datasheet - Page 10

• Manufacturer Part Number: k9f6408u0a
• Description: 8m X 8 Bit Nand Flash Memory
• Manufacturer: Samsung Semiconductor, Inc.

ECC
Error in write or read operation
Over its life time, the additional invalid blocks may develop with NAND Flash memory. Refer to the qualification report for the actual
data.The following possible failure modes should be considered to implement a highly reliable system. In the case of status read fail-
ure after erase or program, block replacement should be done. To improve the efficiency of memory space, it is recommended that
the read or verification failure due to single bit error be reclaimed by ECC without any block replacement. The said additional block
failure rate does not include those reclaimed blocks.
K9F6408U0A-TCB0, K9F6408U0A-TIB0
Program Flow Chart
NAND Flash Technical Notes (Continued)
Program Error
Write
Read
*
No
Single Bit Failure
: Error Correcting Code --> Hamming Code etc.
Failure Mode
Erase Failure
Program Failure
Read Status Registe
Example) 1bit correction & 2bit detection
Write Address
or R/B = 1 ?
I/O 0 = 0 ?
Write Data
I/O 6 = 1 ?
Write 10h
Write 80h
Start
Yes
Yes
No
10
*
Status Read after Program --> Block Replacement
Read back ( Verify after Program) --> Block Replacement
Status Read after Erase --> Block Replacement
Verify ECC -> ECC Correction
: If program operation results in an error, map out
the block including the page in error and copy the
target data to another block.
Detection and Countermeasure sequence
Program Completed
Wait for tR Time
Write Address
If ECC is used, this verification
operation is not needed.
Verify Data
Write 00h
Yes
FLASH MEMORY
or ECC Correction
No
Program Error
*