Is there a way to detect 1ms pulse with voltage of around 300mV?

[KS]

We are already using ADC for battery sense, also tried using ADC and LPCOM but could not get any reliable result.

[ovrebekk]

Hi

I see you already got a lot of good suggestions, but I would like to know what reference you used for the LPCOMP when you tried it?

Probably none of the internal references will cut is, as they could all be above 300mV (depending on your supply voltage).

You can still use an external reference though. You could set up a voltage divider to generate any voltage between 0 and VDD, and use that as reference on either the AREF0 or AREF1 pins.

I haven't tested this myself, but in theory it should allow you to wake up on the 300mV pulse.

You will have to disable the LPCOMP whenever you use the ADC though, which could be a problem depending on how often you get pulses and how critical it is that you detect them all.

Best regards
Torbjørn