Hi,
Recently I designed and made a USB 1.1 Isolator using a ISOUSB111 chip. I designed the PCB with up to 2 amps on the isolated output, hence adding some additional power components, but that doesnt really matter. As soon as I connect any USB device to my computer, it starts to show that some device is constantly being connected and disconnected (over and over again.) I checked for shorts (there were none), I am getting 5V on the output, what could possibly be wrong? I know that USB 1.1 is really forgiving, but I routed a proper differential pair of 90 Ohm with a solid ground plane under the data lines (my PCB is only 2 layers, so the data lines look so wide), is there any chance my problem is related to some EMI issue (if thats even the case with USB 1.1?) Thank you for any advice.
Recently I designed and made a USB 1.1 Isolator using a ISOUSB111 chip. I designed the PCB with up to 2 amps on the isolated output, hence adding some additional power components, but that doesnt really matter. As soon as I connect any USB device to my computer, it starts to show that some device is constantly being connected and disconnected (over and over again.) I checked for shorts (there were none), I am getting 5V on the output, what could possibly be wrong? I know that USB 1.1 is really forgiving, but I routed a proper differential pair of 90 Ohm with a solid ground plane under the data lines (my PCB is only 2 layers, so the data lines look so wide), is there any chance my problem is related to some EMI issue (if thats even the case with USB 1.1?) Thank you for any advice.
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