1. Chapter 12 Filters and Tuned Amplifiers
12.1 Filter transmission, types and specification
12.2 The filter trasnfer function
12.3 Butterworth and Chebyshev filters
12.4 First-order and second-order filter functions
12.11 Tuned amplifiers

2. 12. 1 Filter transmission , types and specification. 12. 1
12.1 Filter transmission , types and specification Filter Transmission. Fig A general two-port network .

4. Fig Filter Types . Fig Ideal transmission characteristics of the four major filter types : (a) low pass (LP), (b) high pass (HP), (c ) bandpass (BP) and (d) bandstop (BS) .

5. 12. 1. 3 Filter Specification. Fig. 12
Filter Specification . Fig Specification of the transmission characteristics of a low pass filter .

6. Fig. 12. 4 Transmission specifications for a bandpass filter
Fig Transmission specifications for a bandpass filter . The filter has a monotonically decreasing transmission in the passband on both sides of the peak frequency .

9. 12.2 The filter transfer function

13. 12. 2 The filter Transfer Function. Fig. 12
12.2 The filter Transfer Function . Fig Pole-zero pattern for the low pass filter whose transmission is sketched in Fig This is a fifth- order filter (N=5)

16. Fig Pole- zero pattern for the bandpass filter whose transmission function is shown in Fig This is a sixth –order filter (N=6) .

22. 12.3 The Butterworth Filters

24. 12. 3 Butterworth and Chebyshev Filters. 12. 3
12.3 Butterworth and Chebyshev Filters The Butterworth filter Fig The magnitude response of a Butterworth filter .

25. The Procedure for finding H(s) for a Given N
1. Find roots of the polynomial 1+(-1)Ns2N
2. Align the left half plane roots to H(s) and the right half plane roots to H(-s) .
3. Combine terms in the denominator of H(s) to form first and second order factors .

27. Fig. 12.9 Magnitude response for Butterworth filters of various order with ε=1

28. Fig Graphical construction for determining the poles of a Butterworth filter of order N .(a) the general case, (b) N=2, (c ) N=3 and (d) N=4 .

30. To Find a Butterworth transfer function that meets transmission specifications of the form in Fig. 12.3

31. ε= passband deviation parameter

35. Fig. 12. 11 Poles of the ninth –order Butterworth filter of Example 12

36. 12. 3. 2 The Chebyshev Filter. Fig. 12
The Chebyshev Filter . Fig Sketches of the transmission characteristics of representative (a) even-order and (b) odd-order Chebyshev filters .

40. Example 12-2

44. 12. 11 Tuned Amplifiers. 12. 11. 1 The basic principle Fig. 12
12.11 Tuned Amplifiers The basic principle Fig Frequency response of a tuned amplifier .