Hi,
From a technical view .. I don´t agree.
Especially with the used terms.
What does active mean?
Usually there is a digital input. and the whole filter is clocked.
E.g for a signed_int16 input: the input range is -32768 ... +32767. There is no "active" and no "inactive" input.
The output is always there it never is "gone". (Same is true for an input.)
E.g for a signed_int16 output: the output range is -32768 ... +32767. There is no "gone".
FIR: the definition of this filter depends only on the input signal.
The "definition" depends on the values (and the count) of the filter taps.
It is a clocked filter. With constant input values the ouptut will usually be stable after exactly n clock cycles (There are exceptions). Where "n" is the count of filter taps.
IIR: the definition of this filter depends on both: the input and the output signals.
I don´t agree. For an ideal IIR filter the response (time) is infinite. And the response is the output.
If your filter has infinte resolution ... then the ouput signal will change for an infinite time... on any input signal (stable or no tstable).
(For an ideal IIR filter there is only one exception: When the initial filter values and the constant input value does not change the ouput signal)
For sure there is only limited resolution. Thus the signal will change until the value down to the LSB is stable.
For real IIR filters the repsponse time will be finite.
Klaus