LMH6655: AMP-oscillate

Part Number: LMH6655


I am using an LMH6655 as a voltage follower between the log-amp AD8310 and the ADC121L02.  
Why does the output sometimes oscillate? The supply rails look clean on the scope.  
How should I select the feedback resistor and capacitor, and what series resistors should I put in the input and output lines to keep the loop stable?

image.pngimage.png

  • Hello Song, 

      Is it oscillating for first circuit configuration (first image), but not for the second circuit configuration (second image) is that correct? If that is correct, then can you try replacing R2054 with a 25Ohm resistor instead of 2kOhm resistor?

    Thank you,

    Sima