The code is running normally on the nRF52840 using the battery when I connect the usb cable the board turns off

Hi

When you say "turns off", does the board start again after (restart), or will it stay off until you remove the USB port?

Regards,
Sigurd Hellesvik

Hey
when I say "turn off", what happens is that all the lights go out and the code that was running stops running and no connected device indication is found on the mac for at least 40 minutes.
(note: I tried several cables, more than one computer and several USB ports)
if I disconnect the usb cable in a few minutes, the application runs again using the battery

When I try the same, it seems to work fine.

nRF52840DK, blinky sample.

LED1 blinks continuously.
nRF Power Source = VDD
SW6 = DEFAULT
I run on only coin-cell battery. LED1 blinks. LED5(For debugger chip) off.
Insert USB micro into J2. LED1 blinks. LED5 on.

My guess is that there is something wrong with your nRF52840DK.

Regards,
Sigurd Hellesvik