Lenovo 300e 2nd Gen

[Dinneke]

smoke/blown U3 (USB-C power) but what part is it?
Schematics available is not the right one
Board: BM5860_V1.3

[mon2]

Re: Lenovo 300e 2nd Gen

Post pics of the logic board and where U3 is located.

[Dinneke]

Re: Lenovo 300e 2nd Gen

here they are

[mon2]

Re: Lenovo 300e 2nd Gen

U3 looks close to the USB 3.0 Type A connector.

Remove all power and check which pin on the connector is close to U3.

From a 50ft view, this appears to be USB 3.0 load switch. This load switch may be a wlcsp package. This is not a type C related controller.

With care, can you remove this damaged part so we can study the PCB pads and underside of the damaged part?

Believe that the only loss here is that the USB 3.0 connector which is nearby will not be functional since it will be lacking the Vbus rail (due to this load switch being blown).

[Dinneke]

Re: Lenovo 300e 2nd Gen

marking looks like NX20P5090

[mon2]

Re: Lenovo 300e 2nd Gen

Indeed...datasheet is attached.

So this load switch is linked to the nearby USB 3.0 connector and acts like an electronic fuse that will turn OFF if the current is exceeded and report this fault to the upstream USB host controller. Windows will then display a pop-up / balloon indicating the error condition.

As you can see, even this load switch has its limit if it is burnt.

The part is not difficult to replace / solder but suggest to watch some videos and use lots of flux. We are soldering 1.4*1.4mm 16 ball WLCSP by hand which can be done after a bit of practice. These are for some repairs of finished PCBAs which are from a fully automated SMT line.

Available in the market:

https://www.findchips.com/search/NX20P5090UK%20

[Dinneke]

Re: Lenovo 300e 2nd Gen

more problems, shorts.

NX20P5090 is in store here.

[mon2]

Re: Lenovo 300e 2nd Gen

more problems, shorts.

Post the details.

[Dinneke]

Re: Lenovo 300e 2nd Gen

Board is scrapped