Band Pass FilterBand-pass filters:There are applications where a particular band, or spread, or frequencies need to befiltered from a wider range of mixed signals. Filter circuits can be designed to accomplishthis task by combining the properties of low-pass and high-pass into a single filter. Theresult is called aband-passfilter. Creating a bandpass filter from a low-pass and high-passfilter can be illustrated using block diagrams: (Figurebelow)System level block diagram of a band-pass filter.What emerges from the series combination of these two filter circuits is a circuit that willonly allow passage of those frequencies that are neither too high nor too low. Using realcomponents, here is what a typical schematic might look like Figurebelow. The response ofthe band-pass filter is shown in (Figurebelow)
Capacitive band-pass filter:The response of a capacitive bandpass filter peaks within a narrow frequency range.