Adafruit Neotrellis Not powering but from Arduino

HI.
I have a Neotrellis and if i power it from the 5v from arduino it works fine.

But i need to power it from other source and i cant make it respond. I try different 5v chargers but nothing…

The ground must be the same from the source of Volt ?

Any idea helps.
Thanks

The ground must be the same from the source of Volt ?

Every electrical circuit must be closed to flow current. If you are not using an opto coupler, or other type of insulator, it is necessary to use a common reference, usually the GND.

Yes. I have try both the ground of the charger and the ground on the arduino with no luck.

Look at the software, does it have a while loop in it that waits until the serial port is available?

How is the Neotrllis an Arduino problem?

It would be better to contact Adafruit about their product.

If both Arduino and Neotrellis is powered by the same adapter, connect Arduino '5V' to Neotrellis 'VIN', and 'GND' to 'GND', and power to '5V' and 'GND'.

You should measure 5V between '5V' and 'GND' on Arduino, and between 'VIN' on Neotrellis and 'GND' on Arduino.