Bill Chun Wai Hung

**Q1)Find** the values of
R1, C1, R2, C2 Using the version of spice that you want, you should be able to
describe the circuit and simulate it.

R1 = 8k ohm

C1 = 1u farad

R2 = 8k ohm

C2 = 1n farad

Low-Pass

f0 = 1/ (2*pi*R1C1) = 20Hz

High-Pass

f1 = 1/ (2*pi*R2C2) = 20kHz

**Q2)Describe** the circuit
using Spice.

with the source file

V_V1
IN 0 DC 0Vdc AC 1Vac

R_R2
0 OUT 1n

E_U4
N01107 0 VALUE {LIMIT(V(N00142,N01107)*1e13,-15V,+15V)}

R_R1
IN N00142
8k

C_C1 0 N00142 1u

C_C2
OUT N01107
8k

**Q3)Set**
an AC analysis to verify the cutoff frequencies

The AC Sweep shows a band-pass filter result with f0 = 20Hz and f1 =20kHz

The plot shows a shape of the bandpass filter result. In which the signal rises (20Hz) and drops later on (20kHz).

However, the Peak voltage in the plot is
only 1.0mV. The cutoff voltage should be close to 0.7V instead of 1mV.