ASSIGNMENT
Course Code 18ESC102A
Course Name ELEMENTS OF ELECTRONICS ENGINEERING
Programme B.Tech. (ME)
Department Mechanical and Manufacturing engg
Faculty FET
Name of the Student MAHESH R
Reg. No 18ETME005025
Semester/Year 1st /2018
Course Leader/s Mrs. Deepthi
i
Declaration Sheet
Student Name MAHESH R
Reg. No 18ETME005025
Programme B.Tech. (ME) Semester/Year 1st/2018
Course Code 18ESC102A
Course Title ELEMENTS OF ELECTRONICS ENGINEERING
Course Date To
Course Leader
Declaration
The assignment submitted herewith is a result of my own investigations and that I
have conformed to the guidelines against plagiarism as laid out in the Student
Handbook. All sections of the text and results, which have been obtained from other
sources, are fully referenced. I understand that cheating and plagiarism constitute a
breach of University regulations and will be dealt with accordingly.
Signature of the
Date
Student
Submission date
stamp
(by Examination &
Assessment Section)
Signature of the Course Leader and date Signature of the Reviewer and date
Part - A
Solution to the question no – 1
A bridge rectifier is an arrangement of four or more diodes in a bridge circuit configuration
which provides the same output polarity for either input polarity it is used for converting an
alternating current into direct current output.
Figure -1.1 power supply circuit
Working
When it is in positive cycle
When A Is positive and B is negative D2 and D4 are conducting D2 and D4 are forward bias
and.D3 and D1 are in reverse bias condition
When it is in negative cycle
During negative half cycle of input D1 and D3 is in forward bias condition and D2 and D4 are in
Reverse bias condition
The peak inverse voltage of bridge wave rectifier = Vm
Advantages of bridge rectifier:
1. The rectification efficiency of full wave rectifier is double of that half a half wave
rectifier
2. Higher output voltage, higher output power and higher Transformer utilisation factor
in case of full wave rectifier
3. The ripple voltage is low and of higher frequency in case of full wave rectifier so simple
filtering circuit is required
4. No Centre tap is required in the Transformer secondary so in case of bridge rectifier
the Transformer required is simpler. IIFA stepping up or stepping down of voltage is
not required Transformer can be eliminated even
5. For a given power output power transformer of smaller size can be used in case of the
bridge rectifier because current in both primary and secondary windings of the supply
Transformer flow for the entire AC cycle
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Disadvantages of bridge rectifier
1.It required for diodes.
2.The use of 2 extra diodes cause and additional voltage drop thereby reducing the output
voltage
An application-converting AC power to DC using the bridge rectifier
Regulated DC power supply is often required for many electronic applications one of the most
reliable and convenient way is to convert the available AC mains power supply into DC supply
these conversion of AC signal to DC signal is done using a rectifier which is basically a system
of diodes it can be half wave rectifier with rectified only one half of the AC signal r a full wave
rectifier with rectified both cycle of AC signal the full wave rectifier can be Centre tapped
rectifier consisting of two diodes are a bridge rectifier consists of four diodes
A regulated DC power supply
A regulated DC power supply consists of the following components
A step down Transformer to convert high voltage AC to low voltage AC
A bridge rectifier to convert the AC into pulsating DC
A filter circuit consists of a capacitor to remove the AC ripples
Regulator IC 7805 to get regulated DC voltage of V
A power supply can by broke down into a series of blocks each of which performs a particular
function a transformer first steps down High Voltage AC to low voltage AC rectifier circuit is
then used to convert AC to DC
The main difference between conventional rectifier and bridge rectifier is that it produces
almost double the output voltage has a full wave Centre tapped Transformer rectifier using
the same secondary voltage the advantage of using this circuit is that no Centre tapped
transformer is required
Single secondary winding is connected to one side of the diode Bridge Network and the load
to the other side when the positive half cycle of the suppose does B1 B2 conduct in a series
wild bio D3 and D4 are reverse bias and the current flows through the load
The main disadvantage of the bridge rectifier is that it needs four diodes Two of which
conduct in alternate half cycles because of this the total voltage drop in diode becomes
double of that in case of centre tap rectifier losses are increased and rectification efficiency
somewhat reduced
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PART B
Solution to question No. B.1:
Fig 1.2
By applying Kirchoff voltage law to the circuit
Vin = IDR1 + IDR2 + VD + V1
Vin - VD - V1 = IDR1 + IDR2
Vin - VD - V1 = ID(R1 + R2)
ID =
.
ID =
ID = 0.0132 A
ID = 13.2 mA
To calculate Va
Va = IDR1
Va = 0.0132*100
Va = 1.325 V
To calculate Vb
Vb = IDR2
= 0.0132*300
= 3.96 V
To calculate V0
V1 = - Vb + V0
V0 = V1 + Vb
<Subject Title> v
V0 = 4 + 3.96
V0 = 7.96 V
B1.1 : To determine the Q point
Apply kirchoff voltage law to the circuit
Vin = IDR1 + IDR2 + VD + V1
When VD =0
Then Vin = IDR1 + IDR2 + V1
Vin - V1 = ID(R1 + R2 )
ID =
ID =
ID = 15 mA
When ID = 0
Vin = IDR1 + IDR2 + VD + V1
Vin = VD + V1
VD = Vin – V1
VD = 10 – 4
VD = 6V
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Solution to the question no : B.2
Figure : 1.3
B 2.1
Identification of circuit
The audio amplifier require voltage of DC voltage of 12 volt and AC input voltage of 6 volt 6
volt to 12volt converter circuit this inverter circuit can provide upto 800mA of 12 v power
from 6v supply
B 2.2
Working:
The change of voltage is the basic principle involved in many of the circuit devices. The voltage
have to be changed from higher to lower and from lower to higher the circuit is audio
amplifier circuit has a simple 6 volt to 12 volt boost converter circuit using transistors that if
we want DC voltage 12 old but we have six old only the circuit can modified DC voltage 6 old
be 12V DC
The principal work on the circuit is Q1 Q2 R1 R2 R3 R4 r5 17 and C2 build the circuit is model
astable multivibrator given output b square wave which be positive pulse signal at have many
frequency and have R6 perform be limit current flow come to reach 2A PNB of Q3 and A Pinch
of UFO in this condition current at floor come in pin may be of Q3 makes Q3 buyers but q4 still
no buyers because of still have no current bias at a PNB when Q3 buyers make have current
flow through l1,D2 change Zd1 one cause drop voltage at ZdZd1 one with be output voltage
and voltage this increases continuously poverty voltage that equal to 12 old bye have r7 B
limit current already changed come in the way PNB of q4 make q4 work we make Q3 stops
bias then make output voltage with zero volt but when positive pulse signal that maid come to
then change come to at R6 then makes Q3 buyers again and work character as before but
there are many speed then we can make output that appears can come out 12 volt
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B 2.3
TABLE : List of Components and it’s values
SL No. LIST OF VALUES OF
COMPONENTS COMPONENTS
1 R1 2.2k Ohm
2 R2 4.7K Ohm
3 R3 4.7K ohm
4 R4 2.2k ohm
5 R5 1K ohm
6 R6 1.5K ohm
7 R7 33Kohm
8 R8 10K ohm
9 C1 0.1uF ceramic disc capacitor
10 C2 0.1uF
11 C3 470uF
12 D1 IN914 diode
13 D2 IN4004 diode
14 D3 12V, 400MW Zener diode
15 Q1 BCS47 NPN Transistor
16 Q2 BCS47 NPN Transistor
17 Q3 BCS47 NPN Transistor
<Subject Title> viii
