Raspberry Pi4 chip blown need ID

[horga83]

Hi All,

I have a RPI4 and the 6 pin chip just behind the USB2 connector is fried.  I have tried to search for the ID which is BJ9uD but alas nothing found.
Can anyone help me out here.

Thanks in advance.
George

[amyk]

Pictures please?

Could be SY8101B.

https://rik174.ru/files/products/izobrazhenie-001_321.1200x800w.jpg?4658e52af253445ca68ee69721bbb804

[horga83]

Yes here is a picture.  I can't get the camera close enough to take a pic but through the microscope it is certainly a BJ9uD
Thanks for your reply I tried to look up the BJ9YK in your link but no luck.
The SY810B could be a candidate.

[amyk]

BJxxx is SY8101B.

As an aside... what is this half-baked piece of crap they call a "schematic"?
https://datasheets.raspberrypi.org/rpi4/raspberry-pi-4-reduced-schematics.pdf
I'm surprised no one has RE'd the whole thing yet, given how many have been made. Shows what the "maker community" is actually capable of...

[horga83]

Thank you very much, now if I can find a place that would sell me a couple, any suggestions?
My normal sources, digikey, mouser, amazon, ebay etc all fail to have them.

[wraper]

BJxxx is SY8101B.

As an aside... what is this half-baked piece of crap they call a "schematic"?
https://datasheets.raspberrypi.org/rpi4/raspberry-pi-4-reduced-schematics.pdf
I'm surprised no one has RE'd the whole thing yet, given how many have been made. Shows what the "maker community" is actually capable of...

It's certainly not SY8101B. It's a USB power switch with current protection. AP2552W6-7 https://www.diodes.com/assets/Datasheets/products_inactive_data/AP255x.pdf (page 13)

[wraper]

BTW does this Raspberry pi boot? Because if it does not boot, you have more problems rather that just a dead USB power switch.

[horga83]

It boots just fine and everything else works just the USB ports are dead.  lsusb shows the hubs so those seem ok.  A device attached to one of the USB ports had a failure and put some unknown amount voltage (likely +15 to 25) on the port.

[wraper]

AP2552W6-7 is out of stock at major distributors. You can also use AP22652AW6-7 instead which is in stock.

[horga83]

I see that, thank you, just ordered a few from Digikey, we'll see what happens.

Thank you all for your help.

[wraper]

As you said a high voltage came in, I looked more and it looks like 100uF cap (connected to USB VBUS) has a hole on it's side and solder mask came off from a copper trace.

[horga83]

Took the chip off and all looks well.

[wraper]