My BBB does not work anymore

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1

Hello,

I mistakenly connected 8V to USB mini connector of BBB board :slight_smile: and it is now not working. The blue power LED lights for a couple miliseconds I think, then it does not light any more. I think the PMU (Power Management Unit) detects a short circuit and switchs the power off.
How can I repair it? Which component shall I look?

Thanks.

2

Not knowing what is damaged, I would say replace the processor. If the LED is flashing that usually means the PMIC is OK, but not having it to look at, you may need to replace the PMIC also.

Or you can request an RMA.

Gerald

3

It should not get damaged because PMIC should handle voltage up to 20V as written in its manual.

4

As written in the manual the 5V switch for the USB host port power will not. The board will be damaged.

Gerald

5

Gerald,

The OP said he applied the 8V to the “USB mini” connector. I take that to mean P4, rather than the USB host port on P3.

P4 does not have a USB power switch. It only connects to the ESD clamp U10, the PMIC USB input, and the SOC USB0_VBUS pins.

The ESD clamp can safely handle the 8V input. The PMIC may be able to handle the 8V input, though it is greater than the recommended operating range max of 5.8V, since it is less that the absolute max of 20 V. However, the AM335x has a absolute max rating of only 5.25 V, so it is quite probably damaged.

Dennis Cote

6

Hi,
I am sorry for late answer, but good news :slight_smile: it works. I don’t know why but it works. I tried with another 5V supply, everything is working now.

I have applied 8V power to USB mini (P4), it stayed there less than a minute, I removed it as soon as possible after I realized. I then connected another 5V supply, blue power LED remained 100ms or 200ms on and then off. Therefore I have thought that it was damaged. Next day I tried another 5V supply and it works. Most probably the first 5V supply didn’t give enough current to boot up.

7

What possesses you people into doing stuff like this ? How can you even mistakenly put more than 5v on a USB mini?

Guys, Gals, if you have money to waste, just send it my way . . .