We use the AD8092
Schematics is here
If signal generator is a sinewave 1.6V peak-to peak, pin 1 is a sinewave 3.2V peak to peak, and pin 7 is a sinewave but the max amplitude saturates at 2.8V.
AD8092A behaves as a rail to rail. while AD8092B does not.
Furthermore the behavior slight changes form one chip to another. Test made on three boards.
Do you have a suggestion?
I suspect the second amplifier is operating outside of the input common mode voltage range of the device. The typical input voltage range can go only to within 1V of the supply, so 2.3V in your case. Try increasing your supply to 4.2V and see if that works.
yes you are right. it was a common mode issue.
By supplying at 5V, the signal rises up to 3.2V peak to peak.