The app shows a list of IIR filters with system structure and its step response. Among them are:
- P system
- PI system
- PD system
- PID system
- PT1 system
- PT2 system
- D system
- IT1 system
- DT1 system
- PDT1 system
- PIDT2 system
This app is supplemented by other apps such as IIR Filter Design and IIR FilterTest, which were deliberately outsourced to the V model.
All three apps together enable any developer to easily design and test any second-order filter. Higher order filters can easily be cascaded, allowing for more complex models and system transfer functions.