TI recently updated their FilterPro™ MFB and Sallen-Key Filter Design software. It is not complete filter design suit and includes only limited amount of physical realizations of second order stages. In fact FilterPro™ is supporting only Multiple Feedback and Sallen-Key realizations of active stages. However, it is doing well what it supposed to do. FilterPro supports Bessel, Butterworth, Linear Phase, Gaussian and Chebyshev approximations. While this is not complete list of commonly used approximations, it represents most of necessary options to support almost any practical design.
Link to Filter design software is here.
You may decide to use different schematic realization, for example, you would like to use Biquad topology. Then you can use values of Q and cutoff frequency’s generated by FilterPro™ and put them into ANALOG FILTER WIZARD™ from Analog Devices. ADI filter wizard will generate RC values for this topology. To do so, you will have to start ADI filter wizard and go to the stage 3, where the wizard will suggest schematic of the stages and frequency response.
The reason why I prefer FilterPro™ from TI over ANALOG FILTER WIZARD™ from Analog Devices is that it generates filter realization that corresponds to the frequency response that you specified. If I specify 0.2 dB ripple in the pass band, this means that it should be no more than 0.2 dB at cutoff frequency. FilterPro™ is working this way and I consider it to be the right way to interpret design specification. Analog Devises software always considers 3 dB to be the end of pass band and it makes it almost useless for some filter approximations.
Also, FilterPro™ allows to specify any value of ripple within pass band and from my point of view it is very convenient feature.
And, with my usual “ paranoia”, I will use LTSPICE to verify filter design.
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