Arduino Nano + external battery

Hi! Can I use plain 5V battery to feed my Arduino Nano board? There is 5V PIN and GROUND PIN; so can I just have 5V battery or do I have to use some sort of controller / resistors ?

I found some answers: "The Arduino Nano can be powered via the mini-B USB connection, 6-20V unregulated external power supply (pin 30), or 5V regulated external power supply (pin 27). The power source is automatically selected to the highest voltage source."

(taken from: )

  • I dont understand, in my opinion it should be "5V with unregulated and 6-20V regulated power supply?"

yes, you can wire 9vdc battery to the Vin pin. You won't get long life for such a battery as they have a pretty low mah rating and are among the most expensive batteries to use Vs the mah provided.


you will kill the voltage regulator by powering it with 9v if the current is too high.. I've killed quite a few of them from 12v and slowly killed them with 9v.