Regarding data sheet of AD9161/9162, I can see the difference between Page4 and Page78 about DAC clock input as follows.
You can see the common-mode voltage is 0.6V and the input impedance is 90ohm on below table.
But you can see 5k ohm and 1.25V on Figure 185 of Page 78 below.
In addition, there is a comment in page 78 that " the input is self biased with a nominal impedance of 90 Ω, it is recommended that the clock source be ac-coupled to the CLK± input pins."
Our customer is confused about the impedance and about the voltage.
Which is correct 90 ohm or 5k+5k=10k ohm? Which is correct 0.6V or 1.25V?