K9F1208B0B SAMSUNG [Samsung semiconductor], K9F1208B0B Datasheet - Page 17

• Manufacturer Part Number: K9F1208B0B
• Description: 64M x 8 Bit NAND Flash Memory
• Manufacturer: SAMSUNG [Samsung semiconductor]

K9F1208R0B
K9F1208B0B
K9F1208U0B
NAND Flash Technical Notes
Error in write or read operation
Within its life time, the additional invalid blocks may develop with NAND Flash memory. Refer to the qualification report for the block
failure rete.The following possible failure modes should be considered to implement a highly reliable system. In the case of status
read failure after erase or program, block replacement should be done. Because program status fail during a page program does not
affect the data of the other pages in the same block, block replacement can be executed with a page-sized buffer by finding an erased
empty block and reprogramming the current target data and copying the rest of the replaced block. In case of Read, ECC must be
employed. To improve the efficiency of memory space, it is recommended that the read failure due to single bit error should be
reclaimed by ECC without any block replacement. The block failure rate in thequalification report does not include those reclaimed
blocks.
ECC
Program Flow Chart
Write
Read
Single Bit Failure
Failure Mode
Erase Failure
Program Failure
: Error Correcting Code --> Hamming Code etc.
Example) 1bit correction & 2bit detection
Program Error
*
(Continued)
No
Read Status Register
Program Completed
Write Address
or R/B = 1 ?
I/O 0 = 0 ?
Write Data
I/O 6 = 1 ?
Write 10h
Write 80h
Start
17
Yes
Yes
*
Status Read after Erase --> Block Replacement
Status Read after Program --> 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
No
FLASH MEMORY
Preliminary