
4.81 The transfer function for the circuit in Figure E4.81 is (see Equation 4.183)
R = 0.2 Ω
R = 0.2 Ω
C
2
=2.5×10
–3
F
C
1
=0.1×10
–3
F
e
i
v
0
v
FIGURE E4.81
V
0
(s)
E
i
(s)
¼
R
2
C
1
C
2
s
2
þ 2RC
2
s þ 1
R
2
C
1
C
2
s
2
þ R(C
1
þ 2C
2
)s þ 1
(a) Convert the system transfer function to a state variable model with output v
0
.
(b) Use the state variable model to find and plot the impulse response.
(c) Find the unit step response of the circuit by inverse Laplace transforming V
0
(s).
(d) Repeat part (c) using the control system toolbox to find the unit step response. Compare
the results from parts (c) and (d).
(e) Approximate the continuous-time transfer function with a discrete-time z-domain transfer ...