alternatives for powering Nano


I read in the forum (a past post) that you can power the Arduino Nano via certain pins.

It appears that you can use either:
A. 5V regulated power source (using 5V and GND)
B. Unregulated 6-12V power source (using VIN and GND)

I've attached sketches of each below of how each would be wired to the Nano. Please let me know if I've missed something, I'm sure I have. And, I'm sure folks have more questions for me.

I have many old wall warts that put out 12V. Then I assume there is a voltage regulator on the Nano which steps the voltage down to 5V. I assume these are still regulated power supplies, correct?

What would be and example of a regulated 5V power supply? Wall wart? My computer?







I think the 6-12V supply might be better as 7-12V to allow for some variation in the dropout voltage of regulators used on clone Nanos. And since those regulators don't have any heat sinks, you're better off using something at the lower end of that range if you have , say, a 9V supply in your junque box. The regulator will generate heat in proportion to the current flowing through it and the voltage drop across it.

Any wall wart that has a USB port to plug into (a USB charger) should be regulated 5V. Same for your computer's USB. 9V and 12V wall warts usually have a barrel connnector or some proprietary connector, and may not be very well regulated - they may have significantly higher voltage under no load.

@ShermanP Thank you for your help. Karma sent. Best, Tony