This is the PCB from https://github.com/TomKeddie/vhs-pcbs/tree/master/usb-isolator. No components are included, PCB only.

I've had some requests over the years for an isolator with inbuilt power supply. Adafruit did such a design last year, the parts cost is about twice this design. I have pcbs from their design for sale here - note that the supply is also 100mA only. The supply in this design is limited only by the current available on the power usb connector (a max of 2A is probably safe).

In one of the earlier SMD workshops I've running at VHS I managed to temporarily kill my new macbook pro when I plugged in a participant's prototype. I revived it by removing the back cover and disconnecting the battery all the time chanting to myself, must get a usb isolator, must get a usb isolator, must get a usb isolator…..

This is a nice simple soldering project that does exactly that, isolates your USB port from connected devices. There are two input usb connectors, one carries data and power from the computer the other supplies power to the output. The output comes from a 3rd USB A connector. There is no power/ground/data connection between the computer and connected devices other than through the isolator chip. This board has two grounds, two power supplies etc.

The isolator chip is an ADUM3160, it is most of the cost of this workshop – “The ADuM3160 is a USB port isolator, based on Analog Devices, Inc., iCoupler® technology. Combining high speed CMOS and monolithic air core transformer technology, this isolation component provides outstanding performance characteristics and is easily integrated with low and full speed USB-compatible peripheral devices.”

I did manage to get some samples from Analog Devices. We’ll be getting the ADUM3160 from Farnell/Element14, you can see more details on the isolator chip at their page.

The ADUM3160 isolator chip is limited to 12Mbps speeds, which are fine for development boards like Arduino etc.

Now shipping RED rev 1.2 of the board. Updates were adjustment of the mounting holes for the USB A socket to make the part easier to mount and addition of power LED indicators to both power supplies. All the documentation on github has been updated.