D **14.60 Design a third-order low-pass filter whose |T| is equiripple in both the passband and the stopband (in the manner shown in Fig. 14.3, except that the response shown is for N = 5). The filter passband extends from ω = 0 to ω = 1 rad/s, and the passband transmission varies between 1 and 0.9. The stopband edge is at ω = 1.2 rad/s. The following transfer function was obtained using filter-design tables: The actual filter realized is to have ωp = 105 rad/s. (a) Obtain the transfer function of the actual filter by replacing s by s/105. (b) Realize this filter as the cascade connection of a first-order LP op amp–RC circuit of the type shown in Fig. 14.8 and a second-order LPN circuit of the type shown in Fig. 14.22(c) with R52 = ∞. Each section is to have a dc gain of unity. Select appropriate component values. (Note: A filter with an equiripple response in both the passband and the stopband is known as an elliptic filter.)