Maximum Arduino Milliamps?

I’m considering a project where I might run 40 mA relays on all 14 of my arudino’s I/O ports. Anyone try this before? Might this be a very bad idea?

Taking this question further, if I bought the new Arduino Mega (with the 54 I/O ports) and ran 54 mA relays, do you think the board would be able to run it okay? Never done anything like this before, so I’m looking for some advice before I start blowing myself up. :slight_smile:


The chips on the standard and mega boards support up to 200mA across all the pins . If you need to run more than that you will need to use external buffers.

there is more on this here: