Device operation

M24M01-R, M24M01-W, M24M01-HR

16/37

Doc ID 12943 Rev 7

Figure 9.

Write mode sequences with WC = 0 (data write enabled)

3.9

ECC (error correction code) and Write cycling

The M24M01-R, M24M01-HR and M24M01-W devices 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.

The M24M01-R, M24M01-HR and M24M01-W devices are qualified at 1 million (1 000 000)

Write cycles, using a cycling routine that writes to the device by multiples of 4-byte words.

Byte Write

Dev sel

Byte addr

Byte addr

Data in

WC

Page Write

Dev sel

Byte addr

Byte addr

Data in 1

WC

Data in 2

AI01106d

Page Write (cont'd)

WC (cont'd)

Data in N

ACK

R/W

ACK

ACK

ACK

ACK

ACK

ACK

ACK

R/W

ACK

ACK