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Arduino Leonardo doesn't work when i connect an AC adapter to it. Answered

I just got an Arduino Leonardo. Everything works great when i am powering it with the usb cable. I can upload sketches and all of that but once i take out the usb cable and i put in the 2.1mm jack of the AC-DC adapter the sketch doesn't run. It is a simple blink L.E.D sketch. Help needed!



6 years ago

Not all 2.1mm jacks are the same, that is the inside diameter of the barrel plug. It takes a (Radio Snacks, Size M) coaxial, 5.5mm O.D. x 2.1mm I.D, positive + center/tip to fit correctly. Is your wall wart 9-12 volts with the configured plug? Your plug may not be touching the outer contact when pushed in. The onboard status LED should at least blink when you plug it in if it is getting power.


Reply 6 years ago

Thank you very much!
The wall adapter wasn't supplying enough power. I changed it and everything works greats!