Active Filter Types

jojo April 14, 2011 No Comments
Types of Active Filters Butterworth, Chebyshev, Bessel and Elliptic filters. There are basically 4 types of active  filters. They are butterworth, Chebyshev, Bessel and Elliptic filters. Butterworth Filter: This filter is also called as maximally flat or flat flat...
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State Variable Filters

jojo April 14, 2011 2 Comments
With the advancement in IC technology, a number of manufacturers now offer universal filters having simultaneous low-pass, high-pass, and band-pass output responses. Notch and all-pass functions are also available by combining these output responses in the uncommitted op-amp. Because...
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All pass filters

jojo April 14, 2011 5 Comments
An all-pass filter is that which passes all frequency components of the input signal without attenuation but provides predictable phase shifts for different frequencies of the input signals. The all-pass filters are also called delay equalizers or phase correctors....
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Band Stop Filter

jojo April 14, 2011 12 Comments
The bandpass fil­ter passes one set of frequen­cies while reject­ing all others. The band-stop filter does just the opposite. It rejects a band of frequencies, while passing all others. This is also called a band-reject or band-elimination filter. Like...
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Band Pass Filters

jojo April 14, 2011 12 Comments
Band Pass Filter A band-pass filter is a circuit which is designed to pass signals only in a certain band of frequencies while attenuating all signals outside this band. The parameters of importance in a bandpass filter are the...
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Higher Order Filters

jojo June 13, 2011 2 Comments
Higher Order Filters From the discussion made so far on the filters, it may be concluded that in the stopband the gain of the filter changes at the rate of 20 db/decade for first-order filters and 40 db/decade for...
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Butterworth Filter

jojo October 7, 2009 No Comments
In many low-pass filter applications it is necessary that the closed-loop gain is as close to unity as possible within the passband. The Butterworth filter is best suited for such applications. This filter is also called a maximally flat...
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Classification of Active Filters

jojo October 7, 2009 62 Comments
The most widely used active filters are (i)                 low-pass (ii)                 high-pass (iii)                band-pass (iv)               band-stop or band reject (also called the band-elimination or notch) and (v)                 all-pass filters. All of these filters use op-amps as the active elements and...
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Active and Passive filters

jojo October 7, 2009 2 Comments
Active and Passive filters – A Comparison: The simplest approach to building a filter is with passive components (resistors, capacitors, and inductors). In the R-F range it works quite well but with the lower frequencies, inductors create problems. AF...
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Filter Circuits – Active Filters

jojo May 5, 2014 10 Comments
Introduction to Filters An electric filter is a network designed to attenuate certain frequencies but pass others without attenuation. A filter circuit, therefore, possesses at least one pass band — a band of frequencies in which the output is...
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