AD9480 ADC has absolute maximum input voltage range as -0.5V..3.8V. But if I use 3.3V supplied ADC driver it is difficult to set 1.9V its output common mode voltage. May I use diff. amps such as AD8138 AD8139 with 5V supply for dc-coupled applications? Is there risk of ADC input damage by overvoltage?
The AD8138 should work as you have configured. The AD8138 can be configured to use an external output common mode (VOCM). Please see the datasheet for AD8138 section "3 V OPERATION" on page 22. I think this explains the mode you are looking for.
FYI, there are other amplifiers we have that can DC couple with a 1.9V output common mode voltage. Please see ADA4930.
Hope this helps.