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Quote:

Originally Posted by squeakr

There is SUPPOSED to be a standard for the mini USB. Although sometimes these cable standards are not followed as you say, but since there is a standard all cables should work as interchangeably as long as the manufacturer followed the standard when they built the cable.

I believe there is a standard, but manufacturers have been expanding on it. In this case, the miniUSB standard (for data transfer and a certain voltage) is expanded to include the ability to accept a higher voltage to allow for faster charging, but the device needs to be able to deal with that higher voltage. You don't want an A/C adapter that puts out a higher voltage than 'normal' USB to be plugged into a device without the proper circuitry to handle that voltage (ie, the miniUSB connector on a digital camcorder), so you change the shape of the plug on the A/C adapter. Now that you've done that, you need to change the shape of the jack on the device to match your plug. But, you keep the shape similar enough to the 'standard' that you can still use the 'standard' plug & cable for data transfers, even if it may mean a slower charge at a lower voltage.