Recently I've been working with an AD9914 board. We powered it with a home-made voltage supply in order to provide the 1.8V and 3.3V necessary. At one point we successfully powered the board, and it was detected by the computer via USB cable. At some point we must have inadvertently adjusted the voltage of the 3.3V supply, which uses a variable resistor, and it's quite possible that the voltage supplied to the 3.3V input exceeded 4V. When supplied the 1.8V and 3.3V, the board now draws far more current than it should based on the datasheet (measured to be approximately 2A through the 3.3V connection). In addition, the computer recognizes a device is connected, but gives an error message that it couldn't connect properly.
I am looking for any input into this matter. It's quite possible that the board has been damaged irreparably, but I would like to know if anybody else has encountered something like this. Please let me know if you have any more questions.