KM29W040AT Datasheet, PDF (10/22 Pages) Samsung semiconductor – 512K x 8 bit NAND Flash Memory

KM29W040AT, KM29W040AIT
FLASH MEMORY
KM29W040A Technical Notes(Continued)
Error in program or erase operation
The device may fail during a program or erase operation.
The following possible failure modes should be considered when implementing a highly reliable system.
Block
Frame
Single Bit
Failure Mode
Erase Failure
Program Failure
Program Failure
("1" --> "0")
Detection and Countermeasure sequence
Read after Erase --> Block Replacement
Status Read after Program --> Block Replacement
Block Verify after Program --> Block Replacement
Block Replacement
During Program operation ;
Buffer
memory
error occurs
When the error happens in Block "A", try to reprogram the
Block A ^{data into another Block "B" by reloading from an external}
buffer. Then, prevent further system access to Block
"A"(by creating a "bad block" table or other appropriate
scheme.)
Block B
During Erase operation ;
When the error occurs after an erase operation, prevent future accesses to this bad block
(again by creating a table within the system or other appropriate scheme.)
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