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Make an USB Hub using HS8836A

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Tom_Kazansky:
Hello!
I have a plan of making an usb hub with integrated macro pad by using HS8836A chip.
I bought the chip https://www.aliexpress.com/item/32856126726.html and wired the board using the diagram in the product page.



the only difference is that I use USB-C instead of USB-MiniB.

after I have soldered necessary components for the hub and plug the board in, I got error "USB not recognized", I go to Device Manager to check the driver and it say "Unknown USB (Device Descriptor Request Failed)".

I wonder what went wrong, anyone know what could have caused this error? maybe I need some specific driver for this chip in Windows 10?  :mad:
I used a multimeter to check for short-circuits but there is none so far.

thanks for reading.

user2021:
Can you share the PCB?
I guess you have a 2 layer board while ignoring impedance which is only fine/valid for short traces.

piit79:
You say you used USB-C instead of USB Mini. Did you add the necessary 5.1k resistors between CC1/CC2 and ground? Although, it should still work even without them when connected to USB 2.0.

Tom_Kazansky:

--- Quote from: piit79 on Thu, 08 July 2021, 08:45:05 ---You say you used USB-C instead of USB Mini. Did you add the necessary 5.1k resistors between CC1/CC2 and ground? Although, it should still work even without them when connected to USB 2.0.

--- End quote ---

I did add the 5.1k resistors to CC lines.

I got the error "USB not recognized" when I plugged my board to USB 2.0 port,
there is no responses if I plug my board to USB 3.1 port.

I'm a bit skeptical about the V3.3, I did connect v3.3 (pin 14) to DCP (pin 12) with some capacitors around that line, is that right or did I misunderstand the diagram?  :(

yui:
i am not sure, but i do not think usb A to C cables have 3.3v so that may be part of the problem, when i checked last time most usb hub chips have their internal 3.3v regulators and exposes it for if you want to use an external one and decoupling and reading a bit about yours it looks to be the case with it too, this 3.3V does not need to be connected anywhere on the usb port, well as far as i know, i found 2 datasheets in Chinese, one toshiba transistor datasheet and a few projects using it, and only putting decoupling on the 3.3V and DCP.
although have you swapped D- and D+? if you did then there would be no communication in USB2.0 but i think USB3 is tolerant to them being swapped, or i may have understood that part wrong. it happens.
and yeah having schematics or board layout would allow to make better guesses, we are a bit blind right now

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