Online tools for active filter design:
Analog Device has tipical filter such as low pass, high pass and band pass filter.
Attention: some circuits generated by defaut do not work!!! You must click the optimization button at the end of the design.
WEBBENCH designer has all type filter.
FilterLab® Filter Design Software ,www.microchip.com. It doesn’t works… From the introduction, it looks great. 🙁
These tools usually generate the filter circuit with their own products. Even Analog Device could give you some equivalent device for the design. However, from my experiance, it works not very well.
Another powerful tool is Matlab. The new version matlab 2017 has integrated many signal processing tools. Many example can be found in its site. And you can evaluate its performance in the whole system with Simulink.
Dr. Lu says:
A filter circuit can be easly generated by software, however, there are many limitations in practice, especially in the active filter design. For the choice of op-amp, we’ll see in the next post.