I recently got this cheap USB dac thats plugged into my pc over USB - B but it still needs Micro USB power for some reason. So I thought I could just connect the 5V from the USB A port to the Micro usb’s. Is there any reason why this doesn’t work?

  • @Mandarbmax
    link
    61 year ago

    It might draw too much power for a single pc USB port to handle reliably. Trying what you suggest probably will not damage anything so give it a try and if it doesn’t work just remove the jumpers and use it as it was designed.

    • ɐɥOOP
      link
      fedilink
      2
      edit-2
      1 year ago

      thanks. Max USB A current is 500mA, right?

      • MaxMalRichtig
        link
        fedilink
        2
        edit-2
        10 months ago

        The specified currents are:

        • USB 2.0 is 500mA,
        • USB 3.0 is 900mA

        Since most USB hubs in PCs are USB 3, you can guess that they can push 900 mA regardless. Also, PCs are using internal USB hubs nowadays and often they don’t regulate a single USB outlet but the cumulated power the hub is pushing. This isn’t necessarily safe, but this makes a couple of hubs capable of pushing 1000mA or even more on a single outlet, even though it is not specified this way.

        All in all: You could be fine by doing this, depending on the overall power draw of your device. But probably working on a USB 3 port.

      • @Mandarbmax
        link
        11 year ago

        I don’t know off hand but that sounds about right.