
R–L–C Circuits and Resonance 157
At resonant frequency, the impedance of the circuit reaches its maximum value and the output
voltage is also maximum. At low and high frequencies, the impedance of the tank circuit goes
low, and hence, the output voltage gets decreased.
4.5.2 Band-stop Filter
A basic parallel resonant band-stop filter has been shown in Figure 4.16 (a). Further, the band-
stop filter response curve is shown in Figure 4.16 (b). The output is taken across the load
resistance R
L
.
Figure 4.16 Band-stop Filter (a) Circuit Diagram and (b) Response
Curve
C
f
f
r
0
V
o
V
o
in
R
L
L
4.6 APPLICATIONS OF RESONANT CIRCUITS
Some of the important ...