have a new set of ADs AD9218 in an updated design.
the reference is measuring 1.31 V (outside the 1.25 V tolerance). pins 5,6,7 (reference and A & B) are all tied together. what could cause the reference to go out of tolerance
The AD9218 VREF output is specified for 1.18V to 1.28V @25C using a nominal 3.0V supply. Can you please confirm your VD supply is 3.0V when you are observing the 1.31V VREF output? It might also be useful if I could contact you directly to obtain more details about your application specific AD9218 schematic.