Working on a design with the ADV7127 and running into some odd behavior. The outupt of the DAC is terminated into a 78.7 ohm resistor to get the output range we are looking for. This is a none video application. The data is being clocked at 20MHz. When the output is stepped form 0x000 to 0x3FF we get an overshoot to the correct voltage and then the output drops to ~70% of expected then ramps to expected voltage in ~100us. I have used an older version of the ADV7127 in a similar application and did not see this type of issue. In that case it was the ADV7127KR50.
Questions:
1) The datasheet is very unclear on the internal refrence. The ADV7127KRUZ140 has an internal refrence, correct?
2) What could be causing the odd behaviour? the voltage rails all look clean and decoupling is performed per the datasheet.
