Hi All - Thanks for all the great comments. B&B does make an USB isolator, but as was pointed out, the speed is limited to 12 Mbps. This is because isolation chip technology has is not capable of high speed data rates provided by USB 2.0 and USB 3.0. Not to worry though, we are actively researching this and I'm confident our engineers will solve this problem. During my travels, I saw many great applicatons of USB "in the field" and the response to this article shows that the technology is moving out of the office. I'm looking forward to writing some applications based articles to demonstrate the unlimited potential for Industrial USB.
Brad, the third photo (BBUSB12.gif)shows burnout of an isolated barrier. One can see the 3 opto isolators and the HALO transformer. That is a 300mils barrier with isolated DC/DC, that should withstand at least 2.5KV of isolation.
This is no ESD or ground loop. This kind of damage can only be produced by lightning strike-class discharges.
I can understand the commotion over the photographs. They are from B&B’s collection of “customer disasters” sent to us over the years – and they are not all related to USB. I have seen many communication boards which show absolutely no sign of damage after a lightning strike but are dead all the same. Brian purposely wanted to illustrate the worst of the worst to drive home the point that isolation can be life saver.
Wow, now that you've commented once, I expect you'll return often and continue to speak up. I am so glad you enjoyed the article. My goal is to post content that is both informative and enjoyable to read! Thanks for commenting.
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