Hey Carlo, I looked closer and saw the RC values, part of the tool I built extracts what is being done from those, looks like this just entering the RC values in the different numbering that I use, So yes Butterworth Q = .707, gain of 30.2V/V and F0=F-3dB =150kHz
Going back and entering those as design targets, and setting a min LG of 20dB, yields a min GBP of 35MHz unity gain stable (to stay simple here)
Your +/-3V supply is a bit odd, but just scanning my table of TI single op amp solutions, give a minimum margin device like the LMV116 - a 12V 45MHz RRout device, there are others of course, but go with this for now, Completing the design showed some pretty high R's - yes, this op amp is very high input noise at 40nV so the tool scaled the R's up to take advantage of that, try a different part, try the OPA835.
And then just for info, here is the open loop OPA835 gain with noise gain and then loop gain, you can see the LG mins right around 20dB ,
Might as well continue on to a TINA sim, this is using the 2017 model update for the OPA835, F-3dB is a little low and that little bump way out is concerning,
I usually run a broadband output noise sim to look for spikes indicating low phase margin - looks ok, no spikes, although I recall wondering if the model Zol was resonant enough in this update,
And then here is the file V9OPA835 150kHz MFB.TSC
All of the insert stuff worked fine this time,
Might as well continue on to a TINA sim, this is using the 2017 model update for the OPA835, F-3dB is a little low and that little bump way out is concerning,
I usually run a broadband output noise sim to look for spikes indicating low phase margin - looks ok, no spikes, although I recall wondering if the model Zol was resonant enough in this update,
And then here is the file V9OPA835 150kHz MFB.TSC
All of the insert stuff worked fine this time,
Hey Carlo, I kind of brushed past the OPA862 as a solution but maybe that was a mistake. It in fact can work fine if you look closely at it, I just doubt all these details were being considered in TI active filter tool.
The word document steps through what I did, here is the final single to diff simulation and then that TINA file. The part is way too fast for this requirement, but if you wanted inverting type low impedance input diff output solution, this will do it actually - we normally use FDA's for that purpose, but not impossible,
Design steps,
Applying the OPA862 as an MFB filter.docx
And then the TINA V9 file, have fun -
