Can I use a Switching power supply w/ the arduino?

I recently moved, and I’m unable to find a regular old fashioned 9V wall-wart style adapter. Everything that is sold here (new zealand) seems to be Switching Mode adapters. My experience with Switching Mode adapters is to avoid them at all costs, but that is because I’m used to doing audio projects.

How would the arduino cope if I fed it 9V from a switching mode regulated wallwart? (such as this:

FWIW, I’m going to be controlling several max7221’s with it.

I was eventually planning on building a larger power supply using a 7805 to power the 7221’s and the arduino (bypassing the arduino’s power regulator, since I’ll have the 7805). I’m used to feeding 7805’s with 9V unregulated wall-warts, not with switching mode wallwarts. So I’m just wondering… is this something that I shouldn’t be doing?


So long as it’s not exceeding 1.5v A (7805) and 9-18 v, it should be fine.

The “switching” feature of the supply just extends your options, it doesn’t introduce any new risks that I can think of.


When I say “Switching power supply”, I mean that it converts the voltage using a switched-mode regulator:

I’m not referring to the fact that it has a switch on the side for multiple voltages.


You may need to introduce a load to keep the power supply on. I’m guessing just the Arduino will not be enough.