M24M02 - read time longer than write time?

Central SUPPORT · ‎2019-02-26

I am working with M24M02 and I measured that it takes 50% longer to read a page than to write a page. Is this normal that read time exceeds write time?

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Central SUPPORT · ‎2019-02-26

Please refer to table 13 (400 kHz AC characteristics) and table 14 (1 MHz AC characteristics) in M24M02 datasheet.

The read time depends on the number of bytes read and on clock frequency fSCL. In fact, M24M01 is capable to run at 1MHz. Faster clock frequency will lead to faster data read out.

Ex: For read of one page (excl. initial 4 bytes instructions & address) 256 bytes read means 256 x 8 bits equals 2048 bits. At 1 MHz we have 2048 * 0.000001 sec = 0.002048 sec (i.e. approx. 2 ms).

Write time is always the same – independent from clock frequency. In datasheet write time tw is specified at 10 ms max for consumer (7ms typical) and 5 ms max for auto (4.5 ms typical).

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Central SUPPORT · ‎2019-02-26

Please refer to table 13 (400 kHz AC characteristics) and table 14 (1 MHz AC characteristics) in M24M02 datasheet.

The read time depends on the number of bytes read and on clock frequency fSCL. In fact, M24M01 is capable to run at 1MHz. Faster clock frequency will lead to faster data read out.

Ex: For read of one page (excl. initial 4 bytes instructions & address) 256 bytes read means 256 x 8 bits equals 2048 bits. At 1 MHz we have 2048 * 0.000001 sec = 0.002048 sec (i.e. approx. 2 ms).

Write time is always the same – independent from clock frequency. In datasheet write time tw is specified at 10 ms max for consumer (7ms typical) and 5 ms max for auto (4.5 ms typical).