Safe to power Activity Board though 5V header?

Phil Pilgrim (PhiPi)

I have an app that requires +5V at more current than the Activity Board can supply. I'm planning to use a 12V-to-5V buck converter. It would be convenient to power the Activity Board through one of its many +5V connections, but I'm not sure what effect this might have on its own upstream regulators, if any.

In the words of Laurence Olivier to Dustin Hoffman in the movie Marathon Man, "Is it safe?"

-Phil

kwinn

If there is no external voltage in to to the regulator it should be ok. Has worked for every 3 terminal linear regulator I have done that to.

Lawson

I'd say that powering the activity board with 5v bypassing the on board regulator is safe. That said, most regulators don't like current running through them in reverse. The typical fix for this is a diode to bypass any reverse current. On the activity board, I'd just jumper Vin to 5v at the servo power input selection jumper. (done this safely on several Proto-boards.) Haven't looked at the schematic though, the data-sheet of the 5v regulator should have relevant info as well.

Marty