Two external switching power step down (3.3 and 5 Volts) and GNDs

Other Hardware General Electronics
1

Hi All,

I' m going to do some electronics but as I'm really new on this matter, I would like to steal a few of your time to ask for advices before burning my Mega 2560.
I need to provide power to 3.3 and 5 volts to Arduino connected stuff by external power sources, to avoid to overload the Arduino power section (I have I2C sensors and GPS etc to power, not enough current from the Arduino board itself so). For this pourpose, I added two external SWITCHING step down power supply of this type you can see here: emmeshop.it. These are small and can do up 3 Amperes each. I know all the GND/negatives should be connected together in these cases but these two are switching step down, so I don't know if in case of switching step down, connecting together the Arduino GND AND the two switching negative poles from the step down, is still safe to be done.

Can I do that ?

Thanks,

Stefano.

2

Can I do that ?

Yes you can. Yes it's safe. Yes you must. Because for it to work in the overall system all powered modules and components wired to the arduino must share a common ground reference.

Lefty

3

Thanks Lefty,

I knew all grounds have to be connected together, I had doubts about the behaviour of the two switching step down. Ok, thank you very much for your advice. I will proceed that way :slight_smile:

Much appreciated.

Stefano.