Department of Electronics
Microelectronics-I
ECE 3138
Lab No:
04
Lab Name:
Clippers and Clampers
Lab Instructor: Tahir Ilyas
Date: 21-Feb-2019
THE UNIVERSITY OF LAHORE
Experiment #04
Clippers and Clampers
Objective
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
To build and understand the operation of clipper circuits.
To build and understand the operation of clamper circuits.
To build and understand the operation of voltage multiplier circuit
Components required
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Diodes D1N4148, D1N750
Resistors 1kΩ, 10kΩ
Capacitors 1uF
Power supply (Variable voltage source)
Function generator
Oscilloscope
Summary of theory
In electronics, a clipper is a device designed to prevent the output of a circuit from exceeding a
predetermined voltage level without distorting the remaining part of the applied signal.
A clipper circuit is made up of linear components like resistors and non linear devices like
junction diodes or transistors, but it does not contain energy-storage elements like capacitors.
The main clipping action is performed by the non linear components. Clipper circuits are used
to select that part of a signal which lies above or below a certain reference voltage level in
signal transmission.
Thus clipper circuits are used for wave form shaping. There are two broad categories of clipper
circuits:
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Parallel unbiased/biased clipper circuits
Series unbiased/biased clipper circuits
This lab will cover the parallel clipper circuits.
Clipping Circuits are also called as Slicers, amplitude selectors or limiters.
A clamper is a circuit that introduces a dc level into an ac signal that is it allows the shifting of
the ac signal along the y-axis in both positive and negative direction. The main clamping action
is performed by the capacitor as it once builds voltage across it and then doesn’t allows itself to
discharge and starts to act as a constant voltage source thus coming in series with the input
signal either being added or subtracted while the diode controls the charging and discharging of
the capacitor. It also prevents a signal from exceeding a certain defined magnitude. It is basically
a peak rectifier circuit with its output taken across the resistor instead of the capacitor. It is also
called as a dc restorer.
A clamper along with a half wave rectifier and a capacitor filter is used to build voltage
multiplier.
Experimental work
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Use function generator to produce a sinusoid of amplitude 10 V and of frequency 1 kHz.
Apply this as Vin at the input of each circuit given below.
Use variable power supply as VDC for biasing the circuits.
Connect the circuits as given below and measure the output waveforms with an
oscilloscope. Draw and label the output waveforms on the plots given .Also give short
explanation for the phenomena observed.
1. Unbiased positive clipper
2. Unbiased negative clipper
3. Biased positive clippers
(a)
(b)
4. Biased negative clippers
(a)
(b)
5. Biased positive and negative clippers
(a)
(b)
6. Zener limiter
7. Negative clampers
(a)
(b)
8. Positive clampers
(a)
(b)
9. Voltage doubler
Simulation on (PSpice/Microsim) soft ware:
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Open the schematics window.
Press “get new part” button to select the parts given below to build the circuits as
shown in figures above one by one.
a) D1N750
b) D1N4148
c) VSIN
d) R
e) C
f) VDC
g) Ground earth
h) Bubble
i) Connecting wires
Place the voltage marker at Vout and Vin to observe the output and input
waveforms.
Select dc bias point from analysis setup and then simulate all the circuits to verify
the results obtained from hardware implementation.