MCF51JF128(2011) データシートの表示（PDF） - Freescale Semiconductor

部品番号

コンポーネント説明

メーカー

MCF51JF128
(Rev.:2011)

Embedded - Microcontrollers

Freescale Semiconductor 

Memories and memory interfaces

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 =

EEPROM – 2 × EEESIZE

EEESIZE

× Write_efficiency × nnvmcycd

where

• Writes_FlexRAM — minimum number of writes to each FlexRAM location

• EEPROM — allocated FlexNVM based on DEPART; entered with 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

• nnvmcycd — data flash cycling endurance

MCF51JF128 Advance Information Data Sheet, Rev. 2, 05/2011.

Freescale Semiconductor, Inc.

Preliminary

29

Share Link: