This filter is current driven and has the formulas given by the two diagram options. The circuit is from an American documentation from the 90s applying to any operational amplifier.
We found this circuit in a Radio Electronics. The circuit can be seen elsewhere on this site. The...
Found in old American documentation, this filter has a 8 dB per octave attenuation. The formulas for...
The circuit presented is from the Linear Applications Handbook of the National Semiconductor of...