Soal dan Penyelesaian Bab 16 Efek Frekuensi (Electronics Principles Seventh Edition-Malvino) menggunakan software Multisim.

1. BAB 16. EFEK FREKUENSI
(Tugas Elektronika Lanjut)
Di susun oleh :
Kelompok 1
Nama NPM
1. Andri Abadi 1215031010
2. Bella Nurbaitty S 1215031016
3. DesiPurnamasari 1215031019
4. Novitiyono Wisnu H 1215031054
5. RisdawatiHutabarat 1215031064
JURUSAN TEKNIK ELEKTRO
FAKULTAS TEKNIK
UNIVERSITAS LAMPUNG
2014

2. EXAMPLE 16-14
Draw the ideal Bode Plot for the lag circuit of Fig 16-18a
SOLUTION :
Figure 16-18 lag circuit its Bode Plot
We can calculate the cutoff frequency:
f2 =
1
2𝜋(5𝑘𝛺)(100 𝑝𝐹)
= 318 kHz
Figure 16-18b shows the ideal Bode plot.
The voltage gain is 0 Db at low
frequencies. The Frequency responses
breaks at 318 kHz and then rolls off at a
rate of 20 Db/decade.
This is result of Bode Plot using Multisim Software.
V1
220 Vpk
1000 Hz
0
R1
5kΩ
C1
100pF
XBP1
IN OUT

3. EXAMPLE 16-19
Using the circuit values shown in Fig-28a, calculate the low-cutoff frequency for each
coupling and bypass capacitor. Compare the results to a measurement using a bode plot.
(use 150 for the dc and ac beta values)
SOLUTION :
In figure 16-28a, we will analyze each coupling capacitor and each bypass capacitor
separately. When analyzing each capacitor, treat the other two capacitors as ac shorts.
From the past dc calculating of this circuit r’e= 22.7 𝛺. The Thevenin resistance facing
the input coupling capacitor is :
R =RG = (β)(r’e)= (150)( 22.7 𝛺) = 3,41 𝑘𝛺
Thefore,
R= 600 𝛺 + (10 𝑘𝛺 || 2,2 𝑘𝛺 || 3,41 𝑘𝛺)
R= 600 𝑘𝛺 + 1,18 𝑘𝛺 = 1,78 𝑘𝛺
Figure 16.28a
CE amplifier using
MultiSim
Figure 18.28b Result a measurement using bode plot by MultiSim
R1
600Ω
C1
470nF
R2
10kΩ
Q1
2N3904
R3
2.2kΩ
R4
3.6kΩ
R5
1000Ω
C2
10µF
C3
2.2µF
R6
10kΩ
10V
VCC
V1
1mVpk
1kHz
0
XBP1
IN OUT

4. EXAMPLE 16.20
Using the circuit values shown in fig 16-28a, calculate the high-frequency cutoff values
for the base bypass circuit and the collector bypass circuit. Use 150 for the beta and
10pF for the stray output capacitance. Compare he results to a bode plot using
simulation software.
SOLUTION :
First determine the values of transistor input and output capacitance 1,8 V and
Vc=6,04V. This results in a collector to base reverse voltage of approximately 4,2 V.
The value of C’e at this reverse voltage is 2,1 pF.
Results of Bode plot using Multisim Software
VDD
9V
R1
2MΩ
R2
150Ω
Q1
2N7000
C1
10µF
R3
10kΩ
R4
1MΩ
R5
600Ω
C3
0.1µF
Vin
50mVrms
0 Hz
0°
XBP1
IN OUT

5. EXAMPLE 16-21
Using the circuit shown in fig 16-32, determine the input-coupling circuit and output-
coupling circuit low frequency cutoff points. Compare the calculated values to a bode
plot using multisim.
SOLUTION :
The Thevenin resistance facing the input-coupling capacitor is :
R= 600 Ω + 200 M Ω|| 1 M Ω = 667 k Ω
And the input-coupling cutoff frequency is :
f1 =
1
2𝜋(667𝑘𝛺)(0.1 𝜇𝐹)
= 2.39 Hz
Next, the Thevenin resistance facing the output coupling capacitor is found by :
R= 150 Ω + 1 kΩ = 1.15 kΩ
And the output coupling cutoff frequency is :
f1 =
1
2𝜋(130𝛺)(10 𝜇𝐹)
= 13.8 Hz
Thefore, the dominant low-frequency cutoff value is 13.8 Hz. The midpoint voltage
gain of this circuit is 22.2 dB. The Bode plot in fig-16-32b shows a 3 Db loss at
approximately 14 Hz. This is very close to the calculated value.
Results of Bode plot using Multisim Software
VDD
9V
R1
2MΩ
R2
150Ω
Q1
2N7000
C1
10µF
R3
10kΩ
R4
1MΩ
R5
600Ω
C3
0.1µF
Vin
50mVrms
0 Hz
0°
XBP1
IN OUT

6. EXAMPLE 16-22
In the MOSFET amplifier circuit of fig 16-32, the 2N700 has these capacitances given
on a data sheets.
Ciss = 60 pF
Coss = 25 pF
Crss = 5.0 pF
If gm = 97 mS, What are the high frequency cutoff values for the gate and drain
circuits? Compare the calculations to a bode plot.
SOLUTION :
The high frequency cutoof frequency measures using multisim is approximately 638
kHz. This somewhat inaccurate result demonsreates the difficulty of choosing the
correct internal capacitance values of the device, which are critical to the calculations.
Results of Bode plot using Multisim Software
VDD
9V
R1
2MΩ
R2
150Ω
Q1
2N7000
C1
10µF
R3
10kΩ
R4
1MΩ
R5
600Ω
C3
0.1µF
Vin
50mVrms
0 Hz
0°
XBP1
IN OUT

7. PROBLEM 16.23
Draw the ideal bodeplot for the lag circuit of fig 16-36a
Results of ideal Bode plot using Multisim Software

8. PROBLEM 16.24
Draw the ideal bodeplot for the lag circuit of fig 16-36b
Results of ideal Bode plot using Multisim Software