4-28 Figure 4-24.—Ac component in an LC choke-input filter. By combining the X_{C} of C1 and the resistance of R_{L} into an equivalent circuit (view B), you will have an equivalent impedance of 265 ohms. As a formula; You now have a voltage divider as illustrated in figure 4-25. You should see that because of the impedance ratios, a large amount of ripple voltage is dropped across L1, and a substantially smaller amount is dropped across C1 and R_{L}. You can further increase the ripple voltage across L1 by increasing the inductance (X_{L} = 2pfL). Figure 4-25.—Equivalent circuit of an LC choke-input filter.