M24128-BF STMICROELECTRONICS [STMicroelectronics], M24128-BF Datasheet - Page 17

• Manufacturer Part Number: M24128-BF
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

M24128, M24C64, M24C32
4.9
Figure 8.
ECC (error correction code) and Write cycling
The M24128-BFMB6 and M24C64-FMB6 salestypes offer an ECC (error correction code)
logic which compares each 4-byte word with its six associated EEPROM ECC bits. As a
result, if a single bit out of 4 bytes of data happens to be erroneous during a read operation,
the ECC detects it and replaces it by the correct value. The read reliability is therefore much
improved by the use of this feature.
Note however that even if a single byte has to be written, 4 bytes are internally modified
(plus the ECC word), that is, the addressed byte is cycled together with the three other bytes
making up the word. It is therefore recommended to write by packets of 4 bytes in order to
benefit from the larger amount of write cycles.
All M24C32, M24C64 and M24128 devices are qualified at 1 million (1 000 000) write
cycles; the M24128-BFMB6 and M24C64-FMB6 are qualified (at 1 million write cycles),
using a cycling routine that writes to the device by multiples of 4-byte words.
WC
Byte Write
WC
Page Write
WC (cont'd)
Page Write
(cont'd)
Write mode sequences with WC = 0 (data write enabled)
Dev Select
Dev Select
ACK
Data in N
R/W
R/W
ACK
ACK
Byte address
Byte address
ACK
ACK
ACK
Byte address
Byte address
ACK
ACK
Data in 1
Data in
Device operation
ACK
ACK
AI01106d
Data in 2
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