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Tenda AC8 AC1200, need help with IC identification

I have a Tenda AC8 or AC1200 WiFi router that powers on but doesn’t work either over WiFi or Ethernet.

Please help me identify this part marked WCBTT. On the pcb it’s marked as U3 - it’s really close to the power input and it gets warm together with the coil that is next to it (around 40 C).

Since there are no shorts to ground on any of the caps or anything obvious I wonder if that chip might be the issue

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Guys, thanks for your comments, but there are no shorts on the board on any of the caps anywhere.

My question is what is that WCBTT chip - I can't find anything on it anywhere - no datasheets, not available for sales etc. So obviously it's a manufacturer's marking and that chip is actually called something else

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@insympathy sorry for using up space on your Question but certain things needed to be clarified.

As for the componetn looks liike there may be other markings on the left side of it? The WCBTT could just be manufacturers markings which will be impossible to solve since a lot of them do not publish those markings. Going by the package, it could be a voltage regulator etc. Let's see if we find out more about the device to narrow it down. Have you used a multimeter and tried to figure the pins out. Pin 1 is commonly VCC?

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No worries, couldn't agree more with your comments 👍🏻.

Actually I have a few updates on this:

1) I tried putting a known good firmware onto the bios chip via CH341 programmer - no change whatsoever

2) Connected to the device via UART - it gets boot looped on "init_ram" message (btw select 38400 bps on UART baud rate to get something readable out of this router)

2) I removed the black shield and found quite a few shorted caps around a RTL8197FH IC. Checked it with a thermal cam - around 90º C, so I ordered a replacement for it - I guess that's our faulty component. Plus it also integrates DRAM in it, so... We'll see :)

I'll update the post as soon as the replacement part arrives and I install it.

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@insympathy awesome troubleshooting. Yes, let us know what you find out once you replace those components. In the meantime we’ll keep searching for info on the elusive WCBTT

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well I replaced the chip - it gets warm - around 40º, so it works, and no shorts were detected anywhere on the board, but router won't start anyway and now it won't post on UART, so I guess I'll call it a day - I did what I could, but you can't win them all :)

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@i_am_the_cosmos @vedangupadhyaya you are continuing to use AI answers. While AI is tolerated for the writing style, AI answers as a whole are not. To be transparent about your use of AI, you MUST state this with your Answer.

Your answers are essentially useless. Anytime you post answers that have lines like " consult with a technician or contact customer support for further assistance" you know your answer is not going to help the OP. You are just posting superficial, regurgitated technobabble, that will not lead to the repair of any device.

You are absolutely missing the purpose of this website. We are trying to empower people to fix their own devices, not to send them to the companies that are not supporting Right to Repair and do not repair devices themselves. Companies that for years put Profit before People/Planet. You only send people to them to achieve more profit and do more damage!

None of your answers are supportive of our efforts. You are not telling OP's what they need to do by posting things like " inspect the area around U3, check for short circuits, replace U3", if you do not state how to check. Ask yourself a Question. Would any of your answers enable the repair of a device? You do know that the answer is NO.

AS I see it, your answers are not meeting community standard. You can use them on websites like Quora etc.but never on here. For now your answers have been isolated without affecting your rep points. While we appreciate your attempts to assist others, ongoing use of AI will not be tolerated. You should aim for quality answers not quantity of answers. You should try and help people, not yourself.

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in_sympathy zal eeuwig dankbaar zijn.
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