K9F2808Q0B Samsung semiconductor, K9F2808Q0B Datasheet - Page 14

• Manufacturer Part Number: K9F2808Q0B
• Description: 16M x 8 Bit NAND Flash Memory
• Manufacturer: Samsung semiconductor

ECC
K9F2808Q0B-DCB0,DIB0
K9F2808U0B-VCB0,VIB0
NAND Flash Technical Notes (Continued)
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 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. 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. To improve the efficiency of mem-
ory space, we recommend using ECC without any block replacement in read or verification failure due to single bit error case. Th e
said additional block failure rate does not include those reclaimed blocks.
Program Flow Chart
Write
Read
Program Error
*
No
Single Bit Failure
Failure Mode
: Error Correcting Code --> Hamming Code etc.
Erase Failure
Program Failure
Read Status Register
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
K9F2808U0B-YCB0,YIB0
K9F2808U0B-DCB0,DIB0
Start
Yes
Yes
No
14
*
Status Read after Program --> Block Replacement
Read back ( Verify after Program) --> Block Replacement
Verify ECC -> ECC Correction
Status Read after Erase --> Block Replacement
: If program operation results in an error, map out
target data to another block.
the block including the page in error and copy the
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
*