Terasic ADA Daughter Card

Curiously, Terasic didn't feel a need to specify a frequency range for the AC-coupled AD and DA. By mini-circuits transformer datasheet, it's 0.4 MHz (-3dB) respectively 1 MHz (-1dB). The DA output can be changed to single-ended by removing the transformer and installing a jumper instead. For the AD inputs, that have a double transformer coupling, there's no easy way, cause the AD inputs must be biased around 1.5V. Single ended operation is possible with some performance degradation, but the level shift is necessary. The best solution would be a true differential amp as AD8132.