Browse Prior Art Database

ECC in 512 Bytes Sector NAND Type FLASH EEPROM

IP.com Disclosure Number: IPCOM000110538D
Original Publication Date: 1992-Dec-01
Included in the Prior Art Database: 2005-Mar-25
Document File: 2 page(s) / 40K

Publishing Venue

IBM

Related People

Asano, H: AUTHOR [+4]

Abstract

This article describes non-volatile memory structure which enables ECC capability in block erase FLASH memory by adding sector erase FLASH EEPROM memory, all of them are off the shelf components and have no redundant bits for additional information area.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

ECC in 512 Bytes Sector NAND Type FLASH EEPROM

       This article describes non-volatile memory structure
which enables ECC capability in block erase FLASH memory by adding
sector erase FLASH EEPROM memory, all of them are off the shelf
components and have no redundant bits for additional information
area.

      The figure shows memory configuration using 4K block erase
FLASH memories for basic area and 512 bytes sector erase FLASH memory
for additional information area.  In this case, 512 bytes are used
for data area and 16 bytes are used for additional information area,
such as ECC bits, current/old status, etc. 4 areas are reserved for
one sector information which allows multiple writing as one sector
status changes. This enables utilizing the  same level of write
endurance FLASH memory for data and information area.

      The number of these modules are calculated by the formula shown
below.
x = (512/N)/(n/512)
y = (M/m)/(512/N/x)
  = 512*M/(m*n)
where
M: data capacity
N: additional information bytes for 1 sector
l: total bytes in one block erase FLASH for data area
m: total bytes in one sector erase FLASH for information area
n: Block size in bytes
x: Number of additional information area for 1 sector
y: sector erase modules for additional information