Lenovo ideapad S540 USB issue

[Nagyesz]

So, there's this Lenovo, the USB is on a separate board, as far as I could tell, I examined it and didn't find anything unusual.
When I checked the board with the multimeter, I didn't find 5V present, instead, there are 3V, 1V, and 0.7V. I'll attach everything I managed to measure

Unfortunately, I couldn't find any documentation, boardview, or anything about this board

Sometimes, Windows displayed the message, "The power consumption has exceeded the power supply capabilities of the receiving hub."

What else should I measure to figure out why the USB isn't working?

gs341 ns-c581 rev 1


a

[mon2]

Somewhere on this or perhaps the main board should be a USB load switch. It is the USB load switch that alerts the host USB controller of an excessive current draw. Very likely that load switch is damaged - most are just crap by design. Once damaged, the VBUS rail is lost and so are the USB functions. You will have to use the DIODE mode of testing from point to point to trace back the VBUS pin of the USB connector till you can load the load switch. Share more details of the load switch once it is found. The load switches are quite common and easy to replace with other brands.

[mon2]

Somewhere on this or perhaps the main board should be a USB load switch. It is the USB load switch that alerts the host USB controller of an excessive current draw. Very likely that load switch is damaged - most are just crap by design. Once damaged, the VBUS rail is lost and so are the USB functions. You will have to use the DIODE mode of testing from point to point to trace back the VBUS pin of the USB connector till you can load the load switch. Share more details of the load switch once it is found. The load switches are quite common and easy to replace with other brands.

[Nagyesz]

Thank you mon2! I found what you mentioned, I'm almost certain about it. This ic is blown up right?



Located on main board part UI1 SN1702001RTER_WQFN16_3X3



I do have lenovo motherboards for parts, is it common to find the same one? Also do you have suggestion where to buy the same ic?

[mon2]

Very good. Indeed the guilty party. You should be able to source through Digikey or Mouser or a donor board.

Part # TPS2546RTER

https://www.ti.com/lit/ds/symlink/tp...google.ca%252F

[Nagyesz]

Thank you, I didn't find similar from my parts so I'm gonna order it.

If it's 99F instead of 998, or if the last segment doesn't match, is that okay? Because I found one that says 2546 TI 99F S244 - Will that work?

[mon2]

The top line of '2546' is the most critical to define this part and we know it is from Texas Instruments (TI). The rest are just manufacturer's datecode / place of manufacturing, etc.

[Nagyesz]

Thank you, I didn't know that. Also, thank you for all your help. I have ordered the part, and once it arrives, I will replace the faulty part.

[Nagyesz]

Update: The IC has arrived, I soldered it on, and the USB is now working perfectly. Thank you Mon2!!