I selected a bandpass filter using the Analog Filter Wizard with the following parameters: Bandpass, 15kHz passband, 130kHz center, 30dB gain, single 5V supply. The other requirement is to filter the input differentially and convert to a single-ended output. I also have in stock the LT6238 (quad) which I would like to use.
The following filter was generated from the AFW: Band-Pass; 4th order Chebyshev 3dB; 15kHz passband; 130kHz center (two stage deliyannis friend with reference).
To make the AFW filter differential it would seem that adding a second mirror image two stage filter chain would suffice. This would include the small value resistors at the four REF locations as well as an additional op-amp for the reference. Please confirm if this is the correct approach or if there is a better solution.
The single-ended conversion would be implemented with an additional single supply op amp stage unless there is an easier way to include the single-ended conversion within the differential filter.
Please advise if there are issues or problems with this approach.
Thanks,
Jim
