DRV2605L: low temperature affects I2C communication

Hi Lenio,

It looks like there are ACKs for the first two bytes, but the error is with the third byte that has a NACK.

I would suspect the I2C timing is marginal and at cold it changes just enough that it causes the failure. You should make sure the I2C timing requirements are being met, per the datasheet.

The rise time for SCL looks fairly slow, so that may be an issue. You can try slowing the clock down or changing the pull-up resistors to a lower resistance to help the rise time. It would be interesting to see what the waveform looks like when it is passing at room temp.

What is the time scale, is SCL running at 400kHz?

Brian

Yes, the clock is at 400kHz. Those are good observations - we'll look into it.