Basics of Electronics Engineering Lab (ECP-1101) School of Electronics and Electrical Engineering CHITKARA UNIVERSITY Chandigarh-Patiala National Highway, Tehsil Rajpura, Distt. Patiala – 140401. Web Site. www.chitkara.edu.in Page | 1 EXPERIMENT NO. 1(A) AIM- Introduction to various electronic components and use of multimeter. APPARATUS: Analog & digital multimeter, resistors, capacitors, diodes, transistor, fuse, dc battery. THEORY: 1. Multimeter: It is one of the most versatile general-purpose instruments capable of measuring dc and ac voltages as well as currents and resistances. The multimeter (or VOM) generally consists of the following elements: A balanced bridge dc amplifier and a PMMC meter. An attenuator in input stage to select the proper voltage range. A rectifier for converting an ac input voltage to proportionate dc value An internal battery and additional circuitry for providing the capability of resistance measurement. A function switch for selecting various measurement functions of the meter such as voltage. In addition, the instrument is usually provided with a built in power supply for operation on ac mains and, in most cases, one or more batteries are provided for operation as a portable test instrument. Digital multimeter (DMM) is basically a digital voltmeter and may be used for the measurement of voltage, current (dc or ac) and resistance. All quantities other than dc voltage are first converted into an equivalent dc voltage by some device. For measurement of resistance, a constant current, depending on the range, supplied from battery or a constant current source is passed through the resistance under measurement and voltage developed across it is measured. The resistance value is displayed in ohms. For measurement of current, the unknown current is passed through a precision resistor in many commercial digital multimeters and the voltage developed across the precision resistor is measured. The Current value is displayed in mA. 2. Resistor: A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element. Resistors act to reduce current flow, and, at the same time, act to lower voltage levels within circuits.
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Basics of Electronics Engineering Lab (ECP-1101)
School of Electronics and Electrical Engineering
CHITKARA UNIVERSITY Chandigarh-Patiala National Highway, Tehsil Rajpura, Distt. Patiala – 140401.
Web Site. www.chitkara.edu.in
Page | 1
EXPERIMENT NO. 1(A)
AIM- Introduction to various electronic components and use of multimeter.
APPARATUS: Analog & digital multimeter, resistors, capacitors, diodes, transistor,
fuse, dc battery.
THEORY: 1. Multimeter: It is one of the most versatile general-purpose instruments
capable of measuring dc and ac voltages as well as currents and resistances. The
multimeter (or VOM) generally consists of the following elements:
A balanced bridge dc amplifier and a PMMC meter.
An attenuator in input stage to select the proper voltage range.
A rectifier for converting an ac input voltage to proportionate dc value
An internal battery and additional circuitry for providing the capability of resistance
measurement.
A function switch for selecting various measurement functions of the meter such as
voltage.
In addition, the instrument is usually provided with a built in power supply for operation
on ac mains and, in most cases, one or more batteries are provided for operation as a
portable test instrument.
Digital multimeter (DMM) is basically a digital voltmeter and may be used for the
measurement of voltage, current (dc or ac) and resistance. All quantities other than dc
voltage are first converted into an equivalent dc voltage by some device.
For measurement of resistance, a constant current, depending on the range, supplied
from battery or a constant current source is passed through the resistance under
measurement and voltage developed across it is measured. The resistance value is
displayed in ohms.
For measurement of current, the unknown current is passed through a precision
resistor in many commercial digital multimeters and the voltage developed across the
precision resistor is measured. The
Current value is displayed in mA.
2. Resistor: A resistor is a passive two-terminal electrical component that implements
electrical resistance as a circuit element. Resistors act to reduce current flow, and, at the
same time, act to lower voltage levels within circuits.
Basics of Electronics Engineering Lab (ECP-1101)
School of Electronics and Electrical Engineering
CHITKARA UNIVERSITY Chandigarh-Patiala National Highway, Tehsil Rajpura, Distt. Patiala – 140401.
Web Site. www.chitkara.edu.in
Page | 2
Figure 1.Resistor color codes
3.Capacitor: A capacitor is a passive two-terminal electrical component that
stores electric energy in an electric field.
The most common kinds of capacitors are:
Ceramic capacitors have a ceramic dielectric.
Film capacitors or plastic film capacitors are non-polarized capacitors with an
insulating plastic film as the dielectric. The plastic films used as the dielectric for
film capacitors are Polypropylene (PP), Polyester (PET), Polyphenylene
sulfide (PPS), Polyethylene naphthalate (PEN), and
Polytetrafluoroethylene or Teflon (PTFE).
Electrolytic capacitors (e-caps) are polarized capacitors whose anode electrode (+)
are made of a special metal on which an insulating oxide layer originates by
anodization (forming), which acts as the dielectric of the electrolytic capacitor.
CHITKARA UNIVERSITY Chandigarh-Patiala National Highway, Tehsil Rajpura, Distt. Patiala – 140401.
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Fig 6 transistor
1) PROCEDURE: 1. Measuring AC/DC voltage: The range selector switch should be in voltage position.
Place the leads of the multimeter across the terminal of the unknown voltage. Note
down the reading.
2. Measuring Resistance: Select the range of resistance and after the selections place
the leads of the multimeter across the terminal of the unknown resistance. Note down
the values.
3. Checking the continuity of wire: Connect the wire across the terminals of
multimeter. If reading comes to zero, wire is continuous.
4. Measuring capacitance: Select the range of capacitance and after the selections
place the leads of the multimeter across the terminal of the unknown capacitance.
Note down the values.
5. Checking Diode: Turn the dial (rotary switch) to Diode Test mode ( ). It may
share a space on the dial with another function. Connect the test leads to the diode.
Record the measurement displayed. Reverse the test leads. Record the measurement
displayed. A good forward-based diode displays a voltage drop ranging from 0.5 to
0.8 volts for the most commonly used silicon diodes. Some germanium diodes have a
voltage drop ranging from 0.2 to 0.3 V.
6. Checking transistor: Hook the positive lead from the multimeter to the BASE (B) of
the transistor. Hook the negative meter lead to the EMITTER (E) of the transistor. For
a good NPN transistor, the meter should show a voltage drop between 0.45V and
0.9V.
7. Typical Specifications of Digital Multimeter:
Ranges : DC voltage upto 1,000 V in 5 ranges
AC voltages upto 750 V in 5 ranges
DC current upto 10 A in 5 ranges
AC current upto 10 A in ranges
Resistance upto 200 M in seven ranges
Basic Accuracy : 0.5% for dc voltages
1% for ac voltages
1% for dc current
Basics of Electronics Engineering Lab (ECP-1101)
School of Electronics and Electrical Engineering
CHITKARA UNIVERSITY Chandigarh-Patiala National Highway, Tehsil Rajpura, Distt. Patiala – 140401.
Web Site. www.chitkara.edu.in
Page | 5
1.2% for ac current
0.8 % for resistance
Display : 3.5 digits, LCD
Power Source : 9 V batteries.
OBSERVATION TABLE :
S.NO ELEMENT ACTUAL
READING
MEASURED
READING WITH
MULTIMETER
RESULT :the basic electronic components have been studied and values of resistance
and capacitances have been measured.
Basics of Electronics Engineering Lab (ECP-1101)
School of Electronics and Electrical Engineering
CHITKARA UNIVERSITY Chandigarh-Patiala National Highway, Tehsil Rajpura, Distt. Patiala – 140401.
Web Site. www.chitkara.edu.in
Page | 6
EXPERIMENT NO. 1(B)
AIM: Verification of Kirchhoff’s current law in D.C circuits on kits.
APPARATUS:
a) Resistors (10Ω, 20Ω, 22Ω, 180Ω, 470Ω, 10Ω, 220Ω)
b) Multimeter
c) Regulated Power supply
d) Connecting leads
e) KCL kits
THEORY:
Kirchhoff’s current law:
It states that algebraic sum of the currents entering any point is equal to the sum of the
currents leaving that point. The point may be the interconnection of one or more
branches. This law is nothing more than a restatement of Principles of conservation of
charge.
i.e.
1
0k
jj
I
CIRCUIT DIAGRAM
Figure 1. (A).1: Circuit diagram for KCL
Basics of Electronics Engineering Lab (ECP-1101)
School of Electronics and Electrical Engineering
CHITKARA UNIVERSITY Chandigarh-Patiala National Highway, Tehsil Rajpura, Distt. Patiala – 140401.
Web Site. www.chitkara.edu.in
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PROCEDURE:
Kirchhoff’s current law: 1. Make the connections as shown in the circuit diagram 1.2
2. Switch on the D.C. supply and set it at 5V.
3. Note down the current readings from the ammeter (A1, A2 and A3)
4. Repeat step 3 for the applied voltage V= 10V, 12V and note down the readings.
5. Switch off the D.C. supply
6. Verify the result with analytical calculations
KCL TRAINER BOARD:
Basics of Electronics Engineering Lab (ECP-1101)
School of Electronics and Electrical Engineering
CHITKARA UNIVERSITY Chandigarh-Patiala National Highway, Tehsil Rajpura, Distt. Patiala – 140401.
Web Site. www.chitkara.edu.in
Page | 8
OBSERVATION TABLE:
KCL: Table for kit
S.No. Input
Supply
Theoretical value(A)
Practical value(A)
I1 I2 I3 Total Current
I= I1+I2+I3
I1 I2 I3 Total Current
I= I1+I2+I3
PRECAUTIONS: 1. Connections should be right and tight.
2. Before connecting the instruments, check the error in instrument.
3. The direction of current and voltage should be identified correctly
4. Multimeter should be in Ammeter mode while measuring current.
CONCLUSION:
Kirchhoff’s current law is verified.
Viva voce Question
1. A branch in a network is said to be active when it contains
A. Resistor
B. Inductor
C. Capacitor
D. source
2. A node in a network is defined as
A. Closed path
B. Junction point of two or more branch
C. group of interconnected networks
D. all of above
3. When resistances are connected in series , then voltage across all the resistances is
A. Equal
B. Unequal
C. Proportional to the square of the current
E. None
4. In the nodal voltage method of analysis , the independent variable is the
A. Branch current
B. Node voltage
Basics of Electronics Engineering Lab (ECP-1101)
School of Electronics and Electrical Engineering
CHITKARA UNIVERSITY Chandigarh-Patiala National Highway, Tehsil Rajpura, Distt. Patiala – 140401.
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Page | 9
C. Branch voltage
D. Mesh current
5. In the networks having N nodes ,the number of independent equations is
A. 2N
B. 2N-1
C. N
D. N-2
6. Nodal voltage method analysis is applicable to the network containing
A. Only current sources
B. only voltage sources
C. Current and voltage sources
D. none
7. When the resistances are in parallel , the voltage across the resistor is
A. Equal
B. Unequal
C. Proportional to square of current
D. none
8. Any closed path formed by the branch in a network is called
A. Loop
B. Mesh
C. Node
D. none
9. Which of the following is not the unit of conductance
A. Mho
B. Siemens
C. Volt/ampere
D. ampere/volt
10. Which of these element in the following is not bilateral
A. Resistor
B. Inductor
C. Capacitor
D. transistor
Basics of Electronics Engineering Lab (ECP-1101)
School of Electronics and Electrical Engineering
CHITKARA UNIVERSITY Chandigarh-Patiala National Highway, Tehsil Rajpura, Distt. Patiala – 140401.
Web Site. www.chitkara.edu.in
Page | 10
EXPERIMENT NO. 1(C)
AIM: Verification of Kirchhoff’s voltage law in D.C circuits on kit.
APPARATUS:
a) Resistors (10Ω, 20Ω, 22Ω, 180Ω, 470Ω, 10Ω, 220Ω)
b) Multimeter
c) Regulated Power supply
d) Connecting leads
e) KVL kit
THEORY:
Kirchhoff’s voltage law: It states that at any time instant the algebraic sum of voltages around a closed circuit or a loop is
zero. That is, for a closed circuit having k elements,
1
0k
jj
V
Where Vj represents the voltage drops of the jth element.
1 2 3......... 0
kv v v v
this statement simply tells us that if we start from a particular junction and go around a closed
circuit so as to come back to the same junction, the net potential drop (or potential rise) is zero,
because we have come back to the point at the same potential.
Figure.1 (B).1: Circuit diagram for KVL
Procedure:
Kirchhoff’s voltage law: 1. Make the connections as shown in the circuit diagram 1.1.
2. Switch ON the D.C. supply and set it at 5V
3. Note down the voltage readings from the voltmeter (V1, V2, and V3).
Basics of Electronics Engineering Lab (ECP-1101)
School of Electronics and Electrical Engineering
CHITKARA UNIVERSITY Chandigarh-Patiala National Highway, Tehsil Rajpura, Distt. Patiala – 140401.
Web Site. www.chitkara.edu.in
Page | 11
4. Repeat the step 3 for applied voltage V= 10V, 12V, and note down the readings.
5. Switch off the D.C. supply
6. Verify the result with analytical calculations.
KVL PANEL:-
OBSERVATION TABLE:-
KVL: Table for kits
S.No. Input
Supply
Theoretical value(A)
Practical value(A)
V1 V2 V3 Total Voltage
V=V1+V2+V3
V1 V2 V3 Total Voltage
V=V1+V2+V3
Basics of Electronics Engineering Lab (ECP-1101)
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CHITKARA UNIVERSITY Chandigarh-Patiala National Highway, Tehsil Rajpura, Distt. Patiala – 140401.
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PRECAUTIONS: 1. Connections should be right and tight.
2. Before connecting the instruments, check the error in instrument.
3. The direction of current and voltage should be identified correctly
4. Multimeter should be in Ammeter mode while measuring current.
CONCLUSION:
KVL is verified.
Viva voce Question:
1. In the mesh current method of analysis , the independent variable is
A. Node current
B. mesh current
C. node voltage
D. none
2. In a network of the number of nodes is N and the number of branches is B , the
number of independent mesh equations are
A. B-n+1
B. b+n+1
C. B+n+1
D. B-N-1
3. Nodal and mesh methods of network can be applied to
A. Independent current sources
B. independent voltages sources
C. dependent current sources
D. none
4. When the circuit is suddenly switched on , transients will occur if it contains elements
which are
A. Resistive and inductive
B. resistive and capacitive
C. Resistive, inductive, capacitive
D. none
5. Equations obtained by applying Kirchhoff’s law to a circuit to study its transient
behavior are
A. Linear algebraic
B. non linear algebraic
C. Differential
D. none
6. Any closed path formed by the branch in a network is called
Basics of Electronics Engineering Lab (ECP-1101)
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CHITKARA UNIVERSITY Chandigarh-Patiala National Highway, Tehsil Rajpura, Distt. Patiala – 140401.
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A. Loop
B. mesh
C. node
D. none
7. Which of the following is not the unit of conductance
A. Mho
B. Siemens
C. Volt/ampere
D. ampere/volt
8. Which of these element in the following is not bilateral
A. Resistor
B. inductor
C. capacitor
D. transistor
9. Which of the following correctly simulates the response of reactive circuit?
A. homogeneous
B. Integro-differential
C. linear
D. All of these
10. A node in a network is defined as
A. Closed path
B. junction point of two or more branch
C. Group of interconnected networks
D. all of above
Basics of Electronics Engineering Lab (ECP-1101)
School of Electronics and Electrical Engineering
CHITKARA UNIVERSITY Chandigarh-Patiala National Highway, Tehsil Rajpura, Distt. Patiala – 140401.
Web Site. www.chitkara.edu.in
Page | 14
EXPERIMENT NO. 2
AIM :- Plot and analyze the forward and reverse characteristics of PN junction Si and Ge diodes and determine their knee and breakdown voltages.
APPARATUS:
a) PN Junction diode,
b) Power supply (0 – 90V)
c) Voltmeters (0 – 3V, 0 – 90 V)
d) Ammeter (0 -15 mA)
e) Ammeter (0 – 1.5 A)
THEORY:
A P-N junction, is formed when p-type semiconductor is suitably joined to n-
type semiconductor. The contact surface so formed is known as PN junction. This diode
has two terminals called anode and cathode.
A curve plotted between voltage across the diode (V) and the current flowing through it
(I) is called VI characteristics of a diode. This is known as response of a P-N junction.
FORWARD BIASING: When positive terminal of battery is connected to p-type semiconductor & negative
terminal of battery is connected to n-type semiconductor of P-N junction, the junction is
said to be forward biased.
REVERSE BIASING: When positive terminal of battery is connected to n-type semiconductor & negative
terminal of battery is connected to p-type semiconductor of P-N junction, the junction is
said to be reverse biased.
CIRCUIT DIAGRAM:
Figure 2.1: Biasing of PN junction diode
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PROCEDURE:
(A) FORWARD BIASING
1. Make the connections as shown in Figure 3.1(a)
2. Connect positive terminal of battery to p-type semiconductor & negative terminal to
n-type semiconductor of a P-N junction.
3. Keep the DPDT switches towards 3 V and 15 mA position.
4. Keep the variable contact of the power supply towards minimum position i.e.
anticlockwise.
5. put the ON/OFF switch to ‘ON’ position. Jewel light will indicate the power supply is
ON.
6. Now with the help of the variable contact of the power supply, starting from zero,
increases DC voltage applied across the diode in small steps of about 0.1V. Note the
voltmeter reading and corresponding reading of current in milliammeter.
7. Plot V – I characteristics taking V on x-axis and I on y-axis.
(B) REVERSE BIASING:
1.Make the connections as shown in the Figure 3.1(b).
2.Keep the DPDT switches towards 90 V & 1.5A position.
3.Keep the variable contact of the power supply towards minimum position i.e.
Anticlockwise.
4.Put the ON/OFF switch to ‘ON’ position. Jewel light will indicate the power supply is
ON.
5.Now with the help of the variable contact of the power supply starting from zero
increase DC voltage in small steps of about 0-2V. Note the voltmeter reading and
corresponding reading of micrometer.
OBSERVATION TABLE:
Basics of Electronics Engineering Lab (ECP-1101)
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PRECAUTIONS:
1. To avoid over heating of diode, current should not be passed for long durations.
2. Voltage applied should be well below the safety limit of the transistor.
3. Connection should be made carefully and must be tight.
GRAPH:
Plot a graph between voltage and current applied across the PN – Junction diode, taking
values of voltage along x-axis & the corresponding value of current along y-axis. Take
the forward voltage VF and forward current IF along positive x-axis and y-axis
respectively. Similarly plot the reverse voltage VR and reverse current IR along negative
x-axis and y-axis respectively.
Basics of Electronics Engineering Lab (ECP-1101)
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Figure: 2.2: Characteristics of PN junction diode
CONCLUSION:
1. The Curve shows that only a very small current flow through the diode during the
initial stage still the potential barrier is wiped-off. Once the potential barrier wiped-
off, current rises quickly
2. The knee voltage of germanium diode is quite lower than the silicon diode. This is
the major
difference between the two types of diodes.
3. Knee Voltage of a diode is……….
4. Breakdown voltage of a diode is………
Viva-Voce Questions
Ques.1. Which of the following is present in the valence band
A. Free electrons
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B. Electrons attached to atoms
C. Holes
D. All of these
Ques.2. Which of the following materials show s the presence of free electrons
A. Conductors
B. Semiconductors
C. Insulators
D. All of these
Ques3. Which of the following applies to P-N junction diode
A. Majority carriers are holes
B. Minority carriers are electrons
C. Penta and trivalent impurities are present
D. All of above
Ques.4. The vicinity of P-N junction is
A. Positively charged
B. Negatively charged
C. Charge free
D. None of these
Ques.5.Which of the following dos not describe the region in the N- type of a P-N junction
diode
A. It has a depletion of electrons
B. It is a positively charged
C. It is a negatively charged
D. All of these
Ques.6.Which of the following represents the Zener effect in P-N junction diode
A. Creation of a high electric field
B. Tearing of the electrons
C. Collision of accelerated electrons with holes
D. All of these
Ques.7. P-N junction diode is used as a voltage regulator in a circuit. To which of the
following category the diode belong to
A. Small signal diode
B. Protection diode
C. Zener diode
D. LED
Ques8. How does the diode current change when the temperature of the intrinsic
semiconductor is increased A. No change
B. Decrease
Basics of Electronics Engineering Lab (ECP-1101)
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C. Increase
D. becomes zero
Ques.9. Which of the following do not require dc power
A. laptop
B. mobile phones
C. extra high voltage power transmission
D. none
Ques.10. Resistivity of a semiconductor
A. Increases linearly
B. Decreases linearly
C. Increases exponentially
D. Decreases exponentially
Basics of Electronics Engineering Lab (ECP-1101)
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EXPERIMENT NO. 3
AIM :- Analyze Zener diode as voltage regulator and observe the output voltage with variable input voltage and fixed load resistance for zener diodes with breakdown voltages of 6 V,8V and 12 V.
APPARATUS:
a) Zener diode kit
b) Power supply
c) Multi meter
d) Connecting leads
THEORY:
A Zener Diode is a special kind of diode which permits current to flow in the forward
direction as normal diode, but will also allow it to flow in the reverse direction when the
voltage is above a certain value - the breakdown voltage known as the Zener voltage.
A zener diode exhibits almost the same properties, except the device is specially
designed so as to have a greatly reduced breakdown voltage, the so-called zener voltage.
By contrast with the conventional device, a reverse-biased zener diode will exhibit a
controlled breakdown and allow the current to keep the voltage across the zener diode
close to the zener breakdown voltage. For example, a diode with a zener breakdown
voltage of 3.2 V will exhibit a voltage drop of very nearly 3.2 V across a wide range of
reverse currents. The zener diode is therefore ideal for applications such as the
generation of a reference voltage (e.g. for an amplifier stage), or as a voltage stabilizer
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PROCEDURE:-
1. Make the connection as shown in diagram.
2. The regulated power supply voltage is increased in steps.
3. The input voltage (Vin) and output voltage (Vout) are observed and then noted in
tabular form.
4. A graph is plotted between input voltage (Vin) and output voltage (Vout).
OBSERVATION TABLE:-
S No.
Zener Diode- V Zener Diode- V
Vin
(V)
Vout
(V)
Vin
(V)
Vout
(V)
PRECAUTION:-
1. The terminal of the zener diode should be properly identified.
2. Should be ensured that the applied voltage do not exceed the ratings of the diode.
3. The connection should be neat and tight.
CONCLUSION:-
Hence the zener diode is used as a voltage regulator.
Viva Voce Questions
Ques.1:- Breakdown region of zener diode is named as ______________.
Ques.2:- Depletion layer of zener diode is _______(thin /thick).
Ques.3:- For voltage regulation zener diode is used in ______ (reverse/forward/no
biasing).
Ques.4:-Can zener be used in forward vias. (True/False)
Ques.5:- Doping material used to manufacture zener diode is_______.
Basics of Electronics Engineering Lab (ECP-1101)
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EXPERIMENT NO. 4
AIM: Study and observe the output waveform of half-wave and full wave rectifiers on CRO and calculate the average and rms values of output voltage and current.
APPARATUS:
a) Half wave and full wave rectifier kit
b) Digital Multimeter
c) Connecting wires
d) CRO
e) CRO probes
THEORY:
Half Wave Rectifier
In Half Wave Rectification, When AC supply is applied at the input, only Positive Half
Cycle appears across the load whereas, the negative Half Cycle is suppressed. How this
can be explained as follows:
During positive half-cycle of the input voltage, the diode D1 is in forward bias
and conducts through the load resistor RL. Hence the current produces an output voltage
across the load resistor RL, which has the same shape as the +ve half cycle of the input
voltage.
During the negative half-cycle of the input voltage, the diode is reverse biased
and there is no current through the circuit. i.e., the voltage across RL is zero. The net
result is that only the +ve half cycle of the input voltage appears across the load. The
average value of the half wave rectified o/p voltage is the value measured on dc
voltmeter.
For practical circuits, transformer coupling is usually provided for two reasons.
1. The voltage can be stepped-up or stepped-down, as needed.
2. The ac source is electrically isolated from the rectifier. Thus preventing
shock hazards in the secondary circuit.
The efficiency of the Half Wave Rectifier is 40.6%
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Full Wave Rectifier
The circuit of a center-tapped full wave rectifier uses two diodes D1&D2.
During positive half cycle of secondary voltage (input voltage), the diode D1 is
forward biased and D2is reverse biased. So the diode D1 conducts and current flows