EN27LN4G08 Datasheet, PDF (14/54 Pages) Eon Silicon Solution Inc. – 4 Gigabit (512M x 8), 3.3 V NAND Flash Memory

Error in Write or Read Operation
EN27LN4G08
Within its lifetime, 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 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 or verification failure due to single bit error should be reclaimed by ECC
without any block replacement. The block failure rate in the qualification report does not include those
reclaimed blocks.
Write
Read
Failure
Erase Failure
Program Failure
Up to eight bits failure
Detection and Countermeasure sequence
Read Status after Erase → Block Replacement
Read Status after Program → Block Replacement
Verify ECC → ECC Correction
ECC:
1. Error Correcting Code --> RS Code or BCH Code etc.
2. Example: 4bit correction / 512 bytes
Program Flow Chart
This Data Sheet may be revised by subsequent versions
14
or modifications due to changes in technical specifications.
©2013 Eon Silicon Solution, Inc., www.eonssi.com
Rev. A, Issue Date: 2013/10/03