Terasic ADA Daughter Card

Hello

The problem has been solved. Source of the problem was 40 pin expansion connector - if we plug ADA board "uncorrectly" we will have "higher" resistance on connection between evaluation and expansion boards. My application works on maximum frequency of D/A converter (125 MHz). For some signals I have to set current strength (for output buffers) about 12 mA or 16 mA to obtain required 3.3V amplitude on digital bus.