I am trying to definitively detect, simply by looking at the state of the D+/- pins of a TPS2511, whether or not there is a device plugged into the USB port. In playing with the EVM and a wide variety of devices (iPhones, Droids, tablets, MP3 players, GPS devices, etc.), it would appear that the answer is yes. That is, once all of the handshaking is complete and the '2511 and downstream device "get to know one another," the DC levels on the D+/- pins are unambiguously different from what they are under a "nothing attached" state. But I want to make sure I'm not just getting lucky and that I merely haven't run a cross a device for which this observation doesn't hold true. If it helps clarify matters, just imagine that I'm designing a system that has a USB charging output and needs to do something special when there's no device attached to the charging output.
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