/diy/ - Do It Yourself

>>2406260
>directly measuring the diff voltage with the MCU
it will be much easier to do with a current sense amp and it's i_bias will almost definitely be lower than an ADC input (unless the ADC already has an amp in it too). Power the amp off the same rails as your current source and that takes care of protection for that section
for the MCU you can use a resistor and zeners or diode clamps to the rails, see picrel.

>>2406334
check the typical coil resistance. if that divided by the nominal voltage is around the nominal current then yes you can just apply a voltage directly.

>>2406519
>ABSOLUTE maximum ratings
anon that is the max current that can be forced through that pin without the pad driver literally melting or latching up
yes you absolutely should use a FET or transistor. Don't forget the flyback diode or your MCU will probably reset every time it turns off the relay (I've seen it happen, it is very annoying...).
Also, since you are switching I presume high power signals, you have decoupling caps on your MCU supplies, right? ... r-right??