I recently built a USB isolator using the ADuM3160. For the power supply I used a Murata isolated power supply that takes in 5V from the host USB and converts it to 3.3V. I've attached the complete schematic here. When I connect the device to the computer running Windows 7, I get a "USB device not recognized" error. There is a small LED on the 3.3V side of the isolator which blinks three times and then shuts down. When I connect the same to a Mac, the LED blinks a few times, stays on for a few seconds and then shuts off. Can't seem to figure out where the problem is.