Electronics sessional
• Course code : CSE – 124
• Marks Distribution
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Attendance
Lab report
Class performance
Lab Final
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10
30
20
40
Details of
Lab Final
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Multiple choice ( MCQ )
Fill in the blanks
True false
Very short notes.
Lab Experiment: 1
Name of the
Experiment:
Half Wave Rectifier
Characteristics.
• Objectives:
• To understand the diode’s
characteristics.
• Construct the half wave
bridge rectifier.
• Explain it’s wave form.
Theory
• In analog electronics, a Diode is a component that
restricts the direction of movement of Charge
Carriers. It allows an Electric Current to conduct in
one direction, but blocks the current in the opposite
direction. One important application of Diodes is in
the design of Rectifier Circuit, which is one of the
important parts of a DC Power Adapter, Figure 1.
Figure 1: Block Diagram of a DC
Power Adapter
• Rectification is the process of converting
Alternating Current (AC) into Direct Current
(DC). AC current and voltage change to
positive and negative polarities alternately
(bidirectional), while DC current and voltage
only has either one polarity (unidirectional).
The electrical devices used to perform
rectification are called Rectifiers. Rectification
is classified as Half-wave or Full-wave, with
Half-wave being the simplest.
Figure 2a: A Diode acts as a Halfwave Rectifier
Figure 2b: The Diode is equivalent to a short
circuit during positive half cycles
Figure 2c: The Diode is equivalent to an open circuit during negative half cycles
Circuit Construction
• Half-wave Rectifiers allow either the positive
or negative half cycles of the AC to pass and
block the other one. It can be implemented by
a Diode. An example of a positive Half-wave
Rectifier is given in Figure 2a. The Diode
conducts during positive half cycles; therefore
it can be treated as a short circuit, Figure 2b.
On the other hand, it blocks the current
during the negative half cycles; therefore it
can be treated as an open circuit, Figure 2c.
Experimented Wave
form:
The input and output
voltage Waveforms of
a Positive Half-wave
Rectifier are shown in
Figure 3a and Figure
3b respectively. The
output is
unidirectional and has
a finite average value,
DC component.
Figure 3a: AC Input Voltage Waveform
Figure 3b: DC Output Voltage Waveform after
Positive Half-wave Rectifier