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MMA8451Q I2C maximum speed

Question asked by John Campbell on Dec 11, 2016
Latest reply on Jan 5, 2017 by John Campbell

It's stated on the first page of the Rev10 datasheet the following:

I2C digital output interface (operates to 2.25 MHz with 4.7 kΩ pullup)

 

Within Section 2.3 table 4 I2C (slave timing values) for SCL clock Low of 1.3 uS and SCL clock High of 600nS.

 

These are the minimum values.

This implies a maximum clock period of  1.9uS or a Clock speed of 526KHz if you use the minimum time allowed for high and low.

 

This doesn't correspond to 2.25MHz.

Question1:   What am I missing?

 

Question 2:   If my micro can support higher I2C rates what is the maximum clock I can run?

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