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USB Voltage Isolator

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oPossum's comments in this post viewtopic.php?f=35&t=2873&start=20#p21804 about connecting BoosterPacks to high voltage (and the advantages of the C2000 LP) got me thinking about an inline USB voltage Isolation device for the MSP430 LaunchPad. I can sacrifice a $4.30 LP if I smoke something in testing but I would rather not smoke my computer.


I found this one for $38 http://microcontrollershop.com/product_info.php?products_id=3769 Anybody used a cheaper/better one?

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Is anyone planning on making Circuits@home boards?

If not, I will make my own version of USB isolator and make it available in 43oh store.

I'm not making anything but software, but I bought one of those, which I might get a chance to use sometime.


If you do one, a suggestion: put a 0.1" PCB 2-pin header on the voltage line from the DC input to the isolated USB 5V so one can attach an ammeter and see total current consumption of whatever's plugged in downstream when it's powered by the USB.

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Didn't really like existing designs, so did this. Still have some work to do.


Mini B or Micro B for host side connection. The full size B has become uncommon, and it's huge.


Full size A for device side connection. This is still what is on most computers, so common cables can be used.


4 power options:

- 2.5 mm coaxial - as used by USB hub, 2.5" external hard drives, etc...

- USB mini B (probably have to trim plug to make it fit)

- 7 pin non-regulated DC-DC converter

- 8 pin regulated DC-DC converter


I was going to put a ADuM5000 on the back, but it is limited to 100 mA and only 33% efficient at best.


Jumpers for speed selection and pushbutton to force enumeration.


Less than 50 mm wide.


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