Hi Se-woong,
I am looking more at the ADC portion of the schematic. I think it looks pretty good, with the following comments/questions.
- The CLK+/- pins are internally biased, so they should be AC coupled to the clock source. I do not see AC coupling capacitors in the schematic, for the clock.
- The VCM pin on the AD9251 is connected directly to R328, R306, R317 and R308. This is OK. One additional thing I would consider is adding pads for additional series resistors after the fanout to channel A and channel B. These could be populated with 0Ohms initially. The intention is to give the flexibility to add some resistance for isolation between channels, if desired.
- What are the differences between this schematic and the one that was used before for the AD9251-65?
- What is the supply voltage for the ADA4937?
- What is the amplitude of the analog input to the ADA4937?
Thank you.
Doug