Sukkur IBA University
Department of Electrical Engineering
Electronic Circuit Design Lab
Handout # 03: Two stage RC coupled Amplifier Design
Criteria
Lab
Exercise
Report
Assessment Rubrics
Score
The data is complete, correct, and clearly reported using advanced
[0.6 Mark]
tools. Analyzes the collected data, explains the results correctly
The data is complete, but some are incorrect, and not clearly reported.
[0.3 Mark]
The analyzed results are inaccurate and not explained correctly.
Inaccurate data presented with no analysis and interpretations
[0.1 Mark]
Submission
 In Time
 3 days late
 1 week late
Time
[0.4 Mark]
[0.2 Mark]
[0.1 Mark]
Total Score
Submission Profile
Name: Jameel Ahmed
Submission date: 12/09/2019
Marks obtained:
Receiving authority name and signature:
Comments:
________________________________________________________________________________
Instructor Signature
Note: Submit this lab hand-out in the next lab with attached solved activities and exercises
Lab Objectives:
To study the voltage gain, frequency response, and Bandwidth of a two stages RC coupled
Amplifier
Lab Hardware and Software Required:
S No.
1
Device
DC Supply voltage
Capacitors
Resistors
Range / Rating
12 V
BC107BP
10 uF 100 uF
(0.220, 1, 5.6,10, 22, 150)KΩ
2
3
4
Signal generator
Oscilloscope
Connecting wires
0.1-1 MHz
0-20 MHz
1A
Quantity
1
2
2
1
1
1
1
4
Circuit Diagram:
Procedure:
1. Connect the circuit diagram as shown in the figure
2. Adjust input signal amplitude in the function generator and observe an amplified
voltage at the output without distortion
3. By keeping input signal voltage, say at 50mV, vary the input signal frequency
from 0 to 1MHz in steps as shown in tabular column and note the corresponding
output voltages.
2
Results
Frequency (Hz)
Output Voltage Vo
Gain
Gain in dB
20
0.175
3.5
10.88
50
0.458
9.16
19.23
100
0.668
13.36
22.52
1K
0.806
16.12
24.15
10K
0.767
15.34
23.72
100K
0.525
10.5
20.42
500K
0.094
1.88
5.48
1M
0.056
1.12
0.984
Frequency Response:Gain in dB
30
Frequency (Hz)
25
20
15
10
5
0
0
200000
400000
600000
800000
1000000
1200000
Название оси
1. Frequency Response plot.
2. Gain ____ 15.923db_____
3. Bandwidth _100 - 100KHz___
Lab Exercises:
1. Measure the individual stage gains of the circuit and compare with theoretical calculations.
2. Design a 3 stage CE amplifier using RC, direct and transformer coupling using Multisim
software and analyse the results.
Detailed readings:
Microelectronic Circuits by M.H. Rashid (International Edition) Chapter 7.
3
Multistage Amplifier Gain on Oscilloscope :
4
Multistage Amplifier Gain On Bode Analyzer:-
5
Multistage Amplifier Breadboard Implementation:
Gain for Calculated and Theoretical Result:The measured gain of multistage amplifier = 15.953db
The theoretical gain of multistage amplifier = 18.5db
6
Multisim Result Schematic Picture:-
Multisim Result Oscilloscope Picture:-
7
Observations:
We observe that the gain of multistage amplifier is very high than single
stage amplifier.
First the required results not come due to high value R3 which is attached with
function generator. Due to which the ac signal does not reach the output. By
decreasing the value of resistor R3 to 1k the required result is obtained.
Conclusion:
The multistage amplifier is used to increase the output gain. Also, we the obtain 0degree phase shift in 2 stage CE amplifier. For this we use the amplifier where we
need 0-degree phase shift. As this circuit has the medium impedance. So, we use
this for impedance matching for voltage and current.
8
3 stage CE amplifier using RC, direct and transformer coupling:Multisim Schematic diagram:
Multimeter Result:
Oscilloscope Waveform of 3 Stage Amplifier:-
9
Analysation
In 3 stage amplifier we observe 180-degree phase shift in input and output signal.
Also, we observe the voltage gain in each stage. In this circuit the dc level come in
place due to direct coupling. So, we use all of these multistage amplifiers for
different circuits.
10