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I have designed an ADC board based on the AD9694.

For the power approx 1V power rails (AVDD1, DVDD, DRVDD1) I followed the AD9694 evaluation board design and used an ADP1762 with the voltage adjust resistor = 6k34 and the same two stage filter circuit.

To ease board design I used LTM8032 and LTM8033 for my input step down converters. The power supplies are sequenced and managed from 2 off UCD90160A.

At commissioning time I noticed that AVDD1 and DVDD1 were approx 0.95 V rather than the nominal 0.975 V and at the minimum recommended value.

From the ADP1762 datasheet, 

Vout = 3.0*6340*50E-6 = 0.951 V   

Has testing shown that the AD9694 performs better with AVDD1, DVDD at the lower limit of 0.95V?

Alternatively, would the design be more tolerant of part to part spread, aging etc if I change the voltage adjustment resistor to 6k49 giving:

Vout = 3.0*6490*50E-6 = 0.9735 V ?