Active band pass filters are simply filters constructed by using operational amplifiers as active devices configured to simulate inductors. Active band pass filters are used largely at audio frequencies where otherwise the size of the inductor would become prohibitive. In this figure is multiple feedback band pass (MFBP) type which uses capacitors of equal value and leads us to simplified calculations.
Finally pick a convenient value for C which if reasonably large, leads to smaller values of resistance and consequently some aid in reducing noise. Valuable feedback (no pun intended) from readers using rate-this-page (see below and on every other page) indicates the following needs clarification. The 100 uF capacitor above is purely part of the power supply reservoir and has nothing to do with the filter itself. The two 10K resistors are part of the power supply biasing of the op amps because we are not using positive and negative power supplies. The capacitor and resistor values are simply the value of C you choose to use and the resistor values result from the following calculations. It's that simple.
Finally pick a convenient value for C which if reasonably large, leads to smaller values of resistance and consequently some aid in reducing noise. Valuable feedback (no pun intended) from readers using rate-this-page (see below and on every other page) indicates the following needs clarification. The 100 uF capacitor above is purely part of the power supply reservoir and has nothing to do with the filter itself. The two 10K resistors are part of the power supply biasing of the op amps because we are not using positive and negative power supplies. The capacitor and resistor values are simply the value of C you choose to use and the resistor values result from the following calculations. It's that simple.
