Beagle Bone Black power LED blinks once when powered


I powered the BBB over the DGND - VDD_5V. But by accident I plugged it into PWR_BUT.

Now it only gives a short blink at the power LED when powered. I know this is a bad sign… But does anybody of you know if this does not mean the end of it and if it can be somehow reset?


It means that you have blown up the power management IC and maybe other parts on the board.


Hi, my Beaglebone Black have the same behavior, gives a short blink at the power LED when powered.
But, I turned on via usb connector with power supply 5V@1A. What may have happened?

Sounds like an overvoltage condition on the 5V DC input may have damaged the DC input. Usually from a cheap 5V power supply. If the USB power works, then the rest of the board is OK.


Sorry, I think you did not understand. I power up the board through USB connector, not DC input. Anyway, nothing else works.

Neither through USB connector nor DC input.

If the BBB will run from USB power, then the BBB is probably OK.

Put an oscilloscope on the output of the power supply that is causing the problem, and watch what the voltage does when you turn things on.

I had a bench power supply (B&W 1550) that when set to 5 Volts, then the output turned on, would throw a transient up to 6 Volts then return to 5 Volts. (The bigger the capacitor across the load, the greater the transient.) This would trip the over-voltage detect in the BBB power supply, which would blink the power LED once, then off after that.

So, make sure the power supply is working properly. Some of the cheap power supplies out there will NOT run a BBB.

— Graham


I do not think the problem is the power sypply. I was using the same power supply before the problem occurred, power supply is functioning normally, I use it to charge my cell phone!

In this video,, I tested two power supplies. The same that I have used to power up through USB connector and a common DC power supply. Nothing else works :frowning:

Hi Graham,

I was thinking about what you said trip the over-voltage detect, and looking at the schematic realized that there is no protection, i.e. ncp349.
So, a small voltage variation, such as 6V, in the USB connector can brick the board?


I thought that it would work on USB, and not on external power supply.

If the situation is that you get the one blink and no boot, is the same for

both USB power and external power, then there is a hard failure of the

Beaglebone. Either a damaged power supply chip, or a short circuit
downstream from there.

— Graham

Hey I am currently experiencing the same problem as you had. Is there a solution or should I buy a new board?

Thank you

Seems in hindsight an error to remove ncp349 from the BBB…

A suggestion might be to reintroduce this power input protection circuit

I would suggest reinstalling a new image of the Linux Distribution. Luckily you’ve also damaged the operating system.

– Fred Gomes

<> escreveu no dia terça, 23/10/2018 à(s) 13:08:

I think its beyond repair, just buy a new one.