K20P81M100SF2_1109 Datasheet, PDF (35/75 Pages) Freescale Semiconductor, Inc – K20 Sub-Family Data Sheet

Peripheral operating requirements and behaviors
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_subsystem =
EEPROM – 2 × EEESPLIT × EEESIZE
EEESPLIT × EEESIZE
× Write_efficiency × n_nvmcycd
where
• Writes_subsystem — minimum number of writes to each FlexRAM location for
subsystem (each subsystem can have different endurance)
• EEPROM — allocated FlexNVM for each EEPROM subsystem based on DEPART;
entered with Program Partition command
• EEESPLIT — FlexRAM split factor for subsystem; entered with the Program
Partition command
• EEESIZE — allocated FlexRAM based on DEPART; entered with Program Partition
command
• Write_efficiency —
• 0.25 for 8-bit writes to FlexRAM
• 0.50 for 16-bit or 32-bit writes to FlexRAM
• n_nvmcycd — data flash cycling endurance
K20 Sub-Family Data Sheet Data Sheet, Rev. 6, 9/2011.
Freescale Semiconductor, Inc.
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