There appears to be a cut and paste error in the AD5370 (16 bit) vs AD5371 (14 bit) datasheets. On page 18 on both datasheets, top of the right hand column it mentions that the default code for X1A and X1B is 5461 for both the 14 bit (AD5371) and the 16 bit (AD5370) Is this correct? I'm guessing should be 21844 (4x5461) for the 16 bit version. Can someone confirm this? If I use the value from the datasheet the power up output voltage using a 3V reference is -3V which doesn't sound right and will not work in my design.
I believe that the default code for the M register should be 0xFFFF and the code for the C register should be 0x8000. This appears to be the same issue as the incorrect X1A and X1B register values. I suspect this is because the AD5371 had these as 14 bit values and the AD5370 has them as 16 bit values so the new values are bit shifted by 2.