Lab #1
EEE392 Measurements and Analog Circuits Lab
Exp. No #1
Date:
DIODE CLIPPERS AND CLAMPERS
OBJECTIVE
The purpose of the experiment is to design and analyze diode clipping, limiting and clamping circuits.
Also to measure the voltage limits of both biased and unbiased clipping circuits and to predict the effect of a
dc bias voltage on clamping circuits.
PRELAB
1. Design and create a SPICE model of positive and negative clippers using diodes with input signal of
5V peak sine wave at 1 kHz and assume suitable reference voltage. Plot the output waveforms and
transfer curve.
2. Design and create a SPICE model of limiter circuits using Zener diode and analyze the waveforms.
3. Design and create a SPICE model of positive and negative clampers using diodes with input signal
of 5V peak sine wave at 1 kHz and assume suitable reference voltage. Plot the output waveforms
and transfer curve. Also vary the load resistance and observe the load limitations.
EQUIPMENT AND COMPONENTS USED
30 MHz Dual Channel Cathode Ray Oscilloscope
3 MHz Function Generator
0-30 V dc dual regulated power supply
4 ½ digit Digital Multimeter
1N4007 Diode
1Z5V6 Zener Diode
Resistor 1 kΩ, ¼W
Electrolytic Capacitor 10µF/25V
Breadboard and Connecting wires
BNC Cables and Probes
THEORY
Clippers

Clipper circuits are wave shaping circuits that has the ability to “clip” off a portion of the input signal
without distorting the remaining part of the alternating waveform.

The half wave rectifier is an example of the simplest form of diode clipper.

Depending on the orientation of the diode, the positive or negative region of the input signal is
“clipped” off.

There are two general categories of clippers: series and parallel. The series configuration is defined
as one where the diode is in series with the load, while the parallel variety has the diode in branch
parallel to the load.
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Department of Electrical & Electronics Engineering, Amrita Vishwa Vidhyapeetham, Coimbatore.
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Lab #1
EEE392 Measurements and Analog Circuits Lab
Limiters

The limiter sets a “limit” in amplitude of an input signal.

Zener diode is used to limit the peak amplitude of the waveform.
Clampers

The clamper circuit, “clamps” a signal to a different dc level.

The network consists of a capacitor, a diode and a resistive element, it can also employ an
independent dc supply to introduce an additional shift.

The magnitude of R and C must be chosen so that the voltage across the capacitor does not
discharge significantly during the interval the diode is non-conducting.

The total swing of the output is equal to the total swing of input signal.
FURTHER READING
1. Paul Horowitz and Winfeld Hill, ‘The Art of Electronics’, Cambridge University Press, New York,
2nd edition, 1989.
CIRCUIT DIAGRAM
Figure 1: Unbiased Series Positive Clipper
Figure 2: Unbiased Series Negative Clipper
Figure 3: Biased Shunt Positive Clipper
Figure 4: Biased Shunt Negative Clipper
Figure 5: Zener diode Limiter
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Department of Electrical & Electronics Engineering, Amrita Vishwa Vidhyapeetham, Coimbatore.
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Lab #1
EEE392 Measurements and Analog Circuits Lab
Figure 6: Unbiased Negative Clamper
Figure 7: Biased Positive Clamper
PRACTICE PROCEDURE
1. Unbiased Clippers
1. Connect the circuit as shown in Figure 1.
2. Apply sine wave of 10Vp-p, 1 kHz from function generator.
3. Observe the input, output waveforms and its transfer characteristics on CRO screen.
Repeat for triangle and square waves of same amplitude.
Repeat the above steps for Figure 2.
Volt/div =
Time/div =
Graph 1: Input sine wave
Volt/div =
Time/div =
Graph 2: Output waveform
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Department of Electrical & Electronics Engineering, Amrita Vishwa Vidhyapeetham, Coimbatore.
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Lab #1
EEE392 Measurements and Analog Circuits Lab
Graph 3: Transfer Characteristics (XY mode)
Volt/div =
Time/div =
Graph 4: Input and output waveform for triangle wave
Volt/div =
Time/div =
Graph 5: input and output for square wave
Inference
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Department of Electrical & Electronics Engineering, Amrita Vishwa Vidhyapeetham, Coimbatore.
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Lab #1
Volt/div =
EEE392 Measurements and Analog Circuits Lab
Time/div =
Graph 6: Output waveform for circuit in fig 2.
Volt/div =
Graph 8:
Time/div =
Graph 7: Transfer Characteristics (XY mode)
Volt/div =
Time/div =
Graph 9:
Inference
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Department of Electrical & Electronics Engineering, Amrita Vishwa Vidhyapeetham, Coimbatore.
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Lab #1
EEE392 Measurements and Analog Circuits Lab
2. Biased Clippers
1. Connect the circuit as shown in Figure 3.
2. Apply sine wave of 10Vp-p, 1 kHz from function generator and 3 V dc from regulated power supply.
3. Observe the input, output waveforms and its transfer characteristics on CRO screen.
Repeat the above steps for Figure 4.
Volt/div =
Time/div =
Graph 10: Output waveform for circuit in fig 3.
Volt/div =
Graph 11: Transfer Characteristics (XY mode)
Time/div =
Graph 12: Output waveform for circuit in fig 4.
Graph 13: Transfer Characteristics (XY mode)
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Department of Electrical & Electronics Engineering, Amrita Vishwa Vidhyapeetham, Coimbatore.
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Lab #1
EEE392 Measurements and Analog Circuits Lab
Inference
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3. Limiters
1. Connect the circuit as shown in Figure 5.
2. Apply sine wave of 20Vp-p, 1 kHz from function generator.
3. Observe the input, output waveforms and its transfer characteristics on CRO screen.
Volt/div =
Time/div =
Graph 14: Output waveform for circuit in fig 5.
Graph 15: Transfer Characteristics (XY mode)
Inference
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Department of Electrical & Electronics Engineering, Amrita Vishwa Vidhyapeetham, Coimbatore.
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Lab #1
EEE392 Measurements and Analog Circuits Lab
4. Clampers
1. Connect the circuit as shown in Figure 6.
2. Apply sine wave of 10Vp-p, 1 kHz from function generator.
3. Observe the input and output waveforms on CRO screen.
Repeat the above steps for figure 7. Apply 5V dc from regulated power supply.
Volt/div =
Time/div =
Graph 16: Output waveform for circuit in fig 6.
Volt/div =
Time/div =
Graph 17: Output waveform for circuit in fig 7.
Inference
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Department of Electrical & Electronics Engineering, Amrita Vishwa Vidhyapeetham, Coimbatore.
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Lab #1
EEE392 Measurements and Analog Circuits Lab
UNDERSTANDING & LEARNING
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Department of Electrical & Electronics Engineering, Amrita Vishwa Vidhyapeetham, Coimbatore.
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Lab #1
EEE392 Measurements and Analog Circuits Lab
RESULTS AND CONCLUSION
POST LAB INFERENCE
1. How do clipper waveforms differ from those expected if ideal diodes are used?
2. Discuss how lowering of load resistance RL on the clamper circuit affects the output.
Prepared by:
Name: __________________________________________
Experiment Date: ……………
Reg. No.: _________________________
ASSESSMENT
Report Submission Date: ……………
Student Task
Submission Delay: …........
Pre-lab Preparation
15
Performance
10
Observation &
Signature
Inference
Max. Marks
Graded Marks
10
Post-lab / Viva-voce
15
Total
50
Department of Electrical & Electronics Engineering, Amrita Vishwa Vidhyapeetham, Coimbatore.
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