Arduino Due Power Problem

I bought an Arduino Due from an authorized dealer, so I assume I'm not dealing with a clone. It works fine under USB power, but if I plug in an external power source to the barrel plug, the USB becomes inactive, and nothing works. The LEDs go out, and it's essentially dead. I'm using the same power sources that I use successfully on an Uno, so I don't think that's the problem. I've tried 9V battery, 12V wall adapter, and the results are the same. Documentation says it'll take up to 16V, center positive polarity on the barrel plug.

Thinking I must have a bad board, I bought another Due from an authorized dealer, and have exactly the same problem with that one.

Has anyone else experienced this? Is this a quality control problem, or am I doing something wrong?

Thanks,

Bill

If you upload successfully a sketch via the programming port and you keep this port plugged, then the sketch should run immediately after. If you upload a sketch via the programming port and you unplug the USB cable ( there is a power down), then you plug again the USB cable, there is a good chance that the sketch won't run until you push the reset button.

If you power your board via the barrel jack, then you plug a USB cable and you upload successfully a sketch, the sketch should run immedialtely after.

If you power the board via the USB cable and you upload successfully a sketch via the programming port, then you unplug the USB cable ( a power down), then you power the board via the barrel jack, there is a good chance that the sketch won't run until you push the reset button.

If one of these scenarios don't work for you, ask a refund to your reseller (maybe an issue with the voltage regulator, some last version boards are faulty).

BTW, there is a workaround if your DUE don't start after power down:

https://forum.arduino.cc/index.php?topic=256771.0

Thank you.

<<If one of these scenarios don't work for you, ask a refund to your reseller (maybe an issue with the voltage regulator, some last version boards are faulty).>>

Do you have any more information about faulty last version boards, or where you got that information?

Thanks,

Bill

An example here:
https://forum.arduino.cc/index.php?topic=551534.0