ADUM3160 communication issue

I constantly get "USB device not recognized". The device works fine (direct connection with usb cable). I measured 5V on VDD1 and the isolated 5V on VDD2.

Schematic is like above, PDEN (pin 4) is connected to VDD1 and PIN (pin 12) is connected to VDD2. I don't have pull-up resistors. Even when I don't even connect my arduino on the right side, my computer still says "USB device not recognized". Connections are good. What could be the problem?

  • 0
    •  Analog Employees 
    on Feb 24, 2021 12:01 PM


    Connecting SPU and SPD to VDD1/VDD2 will set the ADuM3160 to full speed mode. If a low speed peripheral is connected on the downstream side (side 2) then communication won't work.

    Do you just have USB Type B/Type A connectors (and cable to PC/Arduino) on either side of R1/R2 and R3/R4? Is VBUS1 powered only when the PC is connected (USB connector VBUS)? What is providing the 5V required for VBUS2?

    Best regards,