We are using AD8135 as input buffer for AD9235 80 MS/s differential input ADC.
The problem appeared when we try to use it as a single ended input buffer to differential output.
Example: Vcomm = 0.8V (Vdd+ = 3.3V, Vdss = 0V).
Vin = 1V, we expect:
+OUT to be 0.9V,
-OUT to be 0.7V
-OUT never goes below 0.8V.
To fix this we had to add negative supply. This is NOT mentioned in the specs!!!
Can you confirm, or we did something wrong?