TomKeddie shared his USB Isolator in the project log forum:
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.
Via the forum.
I’m curious, the smaller USB connectors seem to have pieces of polyimide tape on them. Is that metal colour or tape? If tape, any reason for it?
It’s tape (most likely kapton). It is fairly common on these connectors, and they arrive like this.
As far as I know, the tape is used to make it easier for Pick and Place machines to pick up the components.
The tape is placed there to allow pick-and-place machines to pick up the part; the vacuum nozzle wouldn’t work on the connectors otherwise, because of the slots and holes.
Also, lol why is there a VHS logo on it? Srsly?
It is known. VHS, Vancouver Hack Space, is the world’s premier hardware decelerator. see
VHSdecel – because slow and fun is better than fast and stressful.
Looks like Vancouver Hacker Space has borrowed the VHS logo, lol
http://vancouver.hackspace.ca/wp/
Ah thanks. I’m sure it’s generic polyimide and not Kapton®. ;-) Just making sure there is no interesting post-assembly reason for the tape to be there…
V. interesting to hear about the tape on top of the connector. I was pondering this myself a few days ago – I thought it was something to do with insulating the connector.
I’ve used the ADUM4160 chip (not quite sure what the difference is) in a custom product, it’s really a fantastic little chip. It’s a good thing to add some filtering to the power supplies on both sides (chip ferrites are good) to cut down the risk of noise, especially if you end up powering the isolated side from a little DC-DC converter as I did.
If anyone’s interested, I decapped one of these chips last year to see what’s inside. It’s quite cute – three separate dies, with the center one containing an array of six tiny transformers. You can just about make out their coils!. There’s some photos and a video at: –
http://imajeenyus.com/electronics/20131025_ic_decapping/index.shtml
VHS = Vancouver Hacker Space ? I thought the stylized typeface Video Home System logo was a trademark, but http://commons.wikimedia.org/wiki/File:VHS_logo.svg claims that logo is public domain- for what that’s worth.
VHS = Vancouver Hacker Space. Surprisingly, Wikipedia claims that well-known VHS logo is public domain- for what that’s worth.
This requires a separate power supply that you can trust. It would be cool to have a version of this board that’s powered from the main USB host, through an isolated flyback converter.