MCF51JU128VHS FREESCALE [Freescale Semiconductor, Inc], MCF51JU128VHS Datasheet - Page 29

• Manufacturer Part Number: MCF51JU128VHS
• Description: MCF51JU128
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

4. Write endurance represents the number of writes to each FlexRAM location at -40°C ≤Tj ≤ 125°C influenced by the cycling
6.4.1.5 Write endurance to FlexRAM for EEPROM
When the FlexNVM partition code is not set to full data flash, the EEPROM data set size
can be set to any of several non-zero values.
The bytes not assigned to data flash via the FlexNVM partition code are used by the
FTFL to obtain an effective endurance increase for the EEPROM data. The built-in
EEPROM record management system raises the number of program/erase cycles that can
be attained prior to device wear-out by cycling the EEPROM data through a larger
EEPROM NVM storage space.
While different partitions of the FlexNVM are available, the intention is that a single
choice for the FlexNVM partition code and EEPROM data set size is used throughout the
entire lifetime of a given application. The EEPROM endurance equation and graph
shown below assume that only one configuration is ever used.
Writes_FlexRAM =
where
Freescale Semiconductor, Inc.
• Writes_FlexRAM — minimum number of writes to each FlexRAM location
• EEPROM — allocated FlexNVM based on DEPART; entered with Program
• EEESIZE — allocated FlexRAM based on DEPART; entered with Program Partition
• Write_efficiency —
• n
endurance of the FlexNVM (same value as data flash) and the allocated EEPROM backup. Minimum value assumes all
byte-writes to FlexRAM.
Partition command
command
nvmcycd
• 0.25 for 8-bit writes to FlexRAM
• 0.50 for 16-bit or 32-bit writes to FlexRAM
— data flash cycling endurance
MCF51JU128 Advance Information Data Sheet, Rev. 1, 08/2011.
EEPROM – 2 × EEESIZE
EEESIZE
Preliminary
× Write_efficiency × n
nvmcycd
Memories and memory interfaces
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