user34101: can I feed my arduino UNO with a 5V cellphone USB power supply ?
Since the arduino board doesn't regulate the 5V from the USB input, is a cellphone power supply sufficiently regulated ?

user-1: Yes. USB is a standard. You can even use 5V power packs for portable gizmos.
Caution: Ken Shirrif have a good post about non-original USB chargers and its perils. (A dozen USB chargers in the lab: Apple is very good, but not quite the best). Read them and learn a lot.
I only use the original charger that comes with the cell or tablet (and that usually last longer that the cell or tablet that it comes with). I don't trust any third party USB charger or car adapter after Ken's analysis

34101: <p>can I feed my arduino UNO with a 5V cellphone USB power supply ?
Since the arduino board doesn't regulate the 5V from the USB input, is a cellphone power supply sufficiently regulated ?</p>
 -1: <p>Yes. USB is a standard. You can even use 5V power packs for portable gizmos.</p>

<p>Caution: Ken Shirrif have a good post about non-original USB chargers and its perils. (<a href="http://www.righto.com/2012/10/a-dozen-usb-chargers-in-lab-apple-is.html" rel="nofollow noreferrer">A dozen USB chargers in the lab: Apple is very good, but not quite the best</a>). Read them and learn a lot.</p>

<p>I only use the original charger that comes with the cell or tablet (and that usually last longer that the cell or tablet that it comes with). I don't trust any third party USB charger or car adapter after Ken's analysis</p>
