[mogui]

I have tried other USB connections for charging as well and they drain the Reader's battery rather than charging it. I have several small chargers that are designed to plug into a mini-USB connection to provide charging power. They do not work with the Reader.

If I had tools and parts here I would make a little breakout board to analyze what is happening. I suspect the Reader has a way of enabling the power connection from the USB port to its charging circuit. Why did Sony design the Reader this way? Maybe they are trying to protect the Reader's charging circuitry from non-compliant USB power supplies, though they are all supposed to be standard. Any thoughts?

Thanks to NatCh for the clarification (see next).