Filters
FILTERS:
Filters of some sort are essential to the operation of most electronic circuits.
Filters and Signals: What Does a
Filter Do?
In circuit theory, a filter is an electrical network that alters the amplitude and/or phase characteristics of a signal with respect to frequency. Ideally, a filter will not add new frequencies to the input signal, nor will it change the component frequencies of that signal, but it will change the relative amplitudes of the various frequency components and/or their phase relationships. Filters are often used in electronic systems to emphasize signals in certain frequency ranges and reject signals in other frequency ranges. Such a filter has a gain which is dependent on signal frequency.
The Basic Filter Types:
There are five basic filter types * Bandpass * Notch. * low-pass. * high-pass * all-pass
BAND PASS:
Bandpass filters are used in electronic systems to separate a signal at one frequency or within a band of frequencies from signals at other frequencies. The number of possible bandpass response characteristics is infinite, but they all share the same basic form.
Notch or Band-Reject:
A filter with effectively the opposite function of the bandpass is the band-reject or notch filter.
Low-Pass:
A third filter type is the low-pass. A low-pass filter passes low frequency signals, and rejects signals at frequencies above the filter's cutoff frequency.
High-Pass:
The opposite of the low-pass is the high-pass filter, which rejects signals below its cutoff frequency.
All-Pass or Phase-Shift:
The fifth and final filter response type has no effect on the amplitude of the signal at different frequencies. Instead, its function is to change the phase of the signal without affecting its amplitude. This type of filter is called an all-pass or phaseshift filter. Approaches To Implementing Filters: Active, Passive, And Switched-Capacitor:
Passive Filters:
The filters made up of
Filters of some sort are essential to the operation of most electronic circuits.
Filters and Signals: What Does a
Filter Do?
In circuit theory, a filter is an electrical network that alters the amplitude and/or phase characteristics of a signal with respect to frequency. Ideally, a filter will not add new frequencies to the input signal, nor will it change the component frequencies of that signal, but it will change the relative amplitudes of the various frequency components and/or their phase relationships. Filters are often used in electronic systems to emphasize signals in certain frequency ranges and reject signals in other frequency ranges. Such a filter has a gain which is dependent on signal frequency.
The Basic Filter Types:
There are five basic filter types * Bandpass * Notch. * low-pass. * high-pass * all-pass
BAND PASS:
Bandpass filters are used in electronic systems to separate a signal at one frequency or within a band of frequencies from signals at other frequencies. The number of possible bandpass response characteristics is infinite, but they all share the same basic form.
Notch or Band-Reject:
A filter with effectively the opposite function of the bandpass is the band-reject or notch filter.
Low-Pass:
A third filter type is the low-pass. A low-pass filter passes low frequency signals, and rejects signals at frequencies above the filter's cutoff frequency.
High-Pass:
The opposite of the low-pass is the high-pass filter, which rejects signals below its cutoff frequency.
All-Pass or Phase-Shift:
The fifth and final filter response type has no effect on the amplitude of the signal at different frequencies. Instead, its function is to change the phase of the signal without affecting its amplitude. This type of filter is called an all-pass or phaseshift filter. Approaches To Implementing Filters: Active, Passive, And Switched-Capacitor:
Passive Filters:
The filters made up of