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I am working on a PCB Design and I need one USB power supply and data. I have read about CC1/CC2 configurations but I'm not sure that putting 5.1 kOhm resistors on CC1 and CC2 will work fine. I have seen one PCB Design like my design, but the designer uses two usb ports:

Schematics

Why doesn't he connect USB2_N and USB2_P directly on DP1, DN1, DP2, DN2?

The designer tells to me this:

"sure you can do that, just means that you may need an adapter if you want to attach a USB device because you are also powering the board through the same connector. You also need a mechanism to detect the device role which means an extra IC to switch between the host and device role."

Thank you so much.

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BY the look at the schematic, they are using the usb-c power only on the connector. Just like a Raspberry Pi's cpu board. CC1 and CC2 are connected as a device, but no data.

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  • \$\begingroup\$ But, It is not better all on the same connector for save connectors? If I would want all on the same connector, Should it work connecting USB Data to USB C Data Connectors with that CC configuration? \$\endgroup\$
    – Juanma
    Commented Apr 15, 2021 at 10:48
  • \$\begingroup\$ Depends on application, but the USB-c is a really cheap 100W connector compared to others that are not massed produced like them. as far as the USB, yes you could connect data lines, however it has to be done with a USB hub controller if you want to share the same data lines with another usb port. \$\endgroup\$ Commented Apr 15, 2021 at 11:15
  • \$\begingroup\$ I want to use the USB only for flashing eMMC of Raspberry, there are other USB ports for other uses, I supose I don't need any hub, right? \$\endgroup\$
    – Juanma
    Commented Apr 15, 2021 at 11:49
  • \$\begingroup\$ I wouldn't see why not, unless the eMMc card does not have a dedicated pins for programming. \$\endgroup\$ Commented Apr 15, 2021 at 11:59
  • \$\begingroup\$ The designer of the board tells to me this: "sure you can do that, just means that you may need an adapter if you want to attach a USB device because you are also powering the board through the same connector you also need a mechanism to detect the device role which means an extra IC to switch between the host and device role" \$\endgroup\$
    – Juanma
    Commented Apr 16, 2021 at 8:15

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