Page 58 - Analog and Digital Filter Design
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Time and Frequency Response
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FREQUENCY
Figure 2.10
Attenuation of the Butterworth Response Values Filter Order (n)
Butterworth Normalized Lowpass Component Values
Butterworth passive lowpass filters have a ladder network of series inductors
with shunt capacitors at their connection nodes. The first component in this
ladder can be either a series inductor or a shunt capacitor; the following com-
ponents then alternate: for example, series L, shunt C, series L, shunt C, and so
on. This is shown in Figure 2.1 1.
Figure 2.1 1
First Component Is Shunt C
