The fact that data and power can be supplied via a single USB connection is generally a very good thing. However, PCs are only going to provide 500mA over a USB port unless your device negotiates for more.
A powered USB hub can be a solution to this problem, but for total independent control of power and data lines, this USB Data/power Merger device allows you to plug in the power independently of the data connection between host and device.
The power side comes in the form of a pair of screw terminals, and data is input via a Micro-B USB input. This would be extremely useful in testing scenarios (like brownout testing), and could serve to isolate a charging device from any possibility of data transfer if just the power lines are used.
If this looks interesting, but you need something a little bit different, why not check out some of the other USB breakout boards and power supplies that Tindie offers? There’s also a listing of rather unusual USB breakouts if you don’t find what you need!
