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Low pass filter with ADA4927 (current feedback, fully differential)

Question asked by erith835 on Jun 2, 2014
Latest reply on Jun 9, 2014 by erith835

How can I add a low pass filter to a design using a current feedback, fully differential amplifier such as the ADA4927?


The bandwidth should be 50-100 MHz.


All suggestions with 1-3 poles are interesting. (And if you have design equations for Butterworth or Inverse Chebyshev I would be really really happy).


None of the OP-amp filter topologies I have found can be used with this amplifier, either because it has current feedback or because it is fully differential.


I my application, the most important characteristic is linearity, i.e. I need low harmonic distortion and low intermodulation distortion. But if  there is now way to add a low pass filter to the ADA4927 I may switch to ADA4938 which has higher harmonic distortion, but has voltage feedback and thereby allow capacitors in the feedback.