Here the stuff provided is related to the intro to discrete devices and circuits.. #engineeringlife #needyones #collegelife #iddcpracticles

1. G H Raisoni Institute of Engineering & Technology, Pune
( An Autonomous Institute Affiliated to SP Pune University, NAAC Accredited A+
Grade )
Practical Experiment
Subject : Introduction to Discrete Devices and Circuits.
Semester I - Academic Year 2020-21
Name ofStudent: DivisionRoll no:
SAKSHI RAMESH GAWADE D D24
Experiment No:1
TITLE : Study of different electronic components.
AIM : To study of different electronic components with their specifications
such as Resistors, Capacitors, LEDs ,Transistors, Inductors , Integrated
Circuits.
APPARATUS : Resistors ,Potentiometers, Capacitors, Inductors
,Transformers ,Fuses, LEDs ,Transistors, , Integrated Circuits.
THOERY :
1.An electronic component is any basic discrete device or physical entity in
an electronic system used to affect electrons or their associated fields.
2.Electronic components are mostly industrial products, available in a
singular form and are not to be confused with electrical elements, which
are conceptual abstractions representing idealized electronic components.
PROCEDURE :

2. RESISTORS
A resistor is a passivetwo-terminalelectrical component that implements electrical
resistanceas a circuit element. The current through a resistor is in direct proportion
to the voltage across the resistor's terminals. This relationship is represented by
Ohm's law. A device used in electrical circuits to maintain a constantrelation
between current flow and voltage. Resistors areused to step up or lower the voltage
at different points in a circuit and to transform a currentsignal into a voltage signal
or vice versa, among other uses. The electrical behaviour of a resistor obeys Ohm's
law for a constant resistance; however, someresistors aresensitiveto heat, light, or
other variables. Resistors areone of the mostused components in a circuit. Most are
colour coded, but some havetheir value in Ohms and their tolerance printed on
them. A multimeter that can check resistancecan also be helpful, providing the
resistor is already removed fromthe board (measuring it while still soldered in can
give inaccurate results, due to connections with the restof the circuit). They are
typically marked with an “R” on a circuit board.
POTENTIOMETERS
Potentiometers are variable resistors. They normally havetheir value marked with
the maximum value in Ohms. Smaller trim pots may usea 3-digit code where the first
2 digits are significant, and the 3rd is the multiplier (basically the number of 0′s after
the first2 digits). For example, code 104 = 10 followed by four 0′s = 100000 Ohms=
100K Ohms. They may also havea letter code on them indicating the taper (which is
how resistancechanges in relation to how far the potentiometer is turned). They are
typically marked with an “VR” on a circuit board.

3. A light-emitting diode (LED) is a semiconductor device that emits visible
light when an electric current passes through it. The light is not particularly
bright, but in most LEDs it is monochromatic, occurring at a
single wavelength. The output from an LED can range from red (at a
wavelength of approximately 700 nanometers) to blue-violet (about 400
nanometers). Some LEDs emit infrared (IR) energy (830 nanometers or
longer); such a device is known as an infrared-emitting diode (IRED).
CAPACITORS
A capacitor (originally known as a condenser) is a passivetwo-terminalelectrical
component used to store energy electrostatically in an electric field. By contrast,
batteries store energy via chemical reactions. The forms of practical capacitors vary
widely, but all contain at least two electrical conductors separated by a dielectric
(insulator); for example, one common construction consists of metal foils separated
by a thin layer of insulating film. Capacitors are widely used as parts of electrical
circuits in many common electrical devices. Capacitors are also very commonly used.
A lot havetheir values printed on them, some are marked with 3-digit codes, and a

4. few are colour coded. The same resources listed above for resistors can also help you
identify capacitor values. They are typically marked with an “C” on a circuit board.
INDUCTORS
An inductor, also called a coil or reactor, is a passivetwo-terminalelectrical
component which resists changes in electric currentpassing through it. Itconsists of
a conductor such as a wire, usually wound into a coil. When a currentflows through
it, energy is stored in a magnetic field in the coil. When the currentflowing through
an inductor changes, the time-varying magnetic field induces a voltage in the
conductor, according to 4 Faraday’s law of electromagnetic induction, which by
Lenz's law opposes the change in currentthat created it. Inductors, also called coils,
can be a bit harder to figure out their values. If they are color coded, the resources
listed for resistors can help, otherwisea good meter that can measure inductance
will be needed. They are typically marked with an “L” on a circuit board.

5. TRANSFORMERS
A transformer is a static electrical device that transfers energy by inductive coupling
between its winding circuits. A varying currentin the primary winding creates a
varying magnetic flux in the transformer's coreand thus a varying magnetic flux
through the secondary winding. This varying magnetic flux induces a varying
electromotive force(emf) or voltage in the secondary winding. Transformersare
normally pretty easy to identify by sight, and many havetheir specs printed on them.
They are typically marked with an “T” on a circuit board.
FUSES
In electronics and electrical engineering, a fuseis a type of low resistanceresistor
that acts as a sacrificialdevice to provideovercurrentprotection, of either the load or
sourcecircuit. Its essentialcomponent is a metal wire or strip that melts when too
much currentflows, which interrupts the circuit in which it is connected. Short
circuit, overloading, mismatched loads or device failure are the prime reasons for
excessivecurrent. A fuse interrupts excessivecurrent (blows) so that further damage
by overheating or fire is prevented. Fuses can be easy to identify, and typically have
their voltage and amperage rating marked on them.
LED AND LED DISPLAY
A light-emitting diode (LED) is a semiconductor light source. LEDs are used as
indicator lamps in many devices and are increasingly used for other lighting. LEDs

6. emitted low-intensity red light, but modern versions areavailable across thevisible,
ultraviolet, and infrared wavelengths, with very high brightness.
TRANSISTORS
A transistor is a semiconductor device used to amplify and switch electronic signals
and electrical power. Itis composed of semiconductor material with at least three
terminals for connection to an external circuit. A voltage or currentapplied to one
pair of the transistor's terminals changes the current through another pair of
terminals. Becausethe controlled (output) power can be higher than the controlling
(input) power, a transistor can amplify a signal. Today, sometransistors arepackaged
individually, but many more are found embedded in integrated circuits. Transistors
(typically marked with an “Q” on a circuit board).
INTEGRATED CIRCUITS
An integrated circuit or monolithic integrated circuit (also referred to as an IC, a chip,
or a microchip) is a set of electronic circuits on one small plate ("chip") of
semiconductor material, normally silicon. This can be made much smaller than a
discrete circuit made fromindependent components. Integrated circuits are used in
virtually all electronic equipment today and haverevolutionized the world of
electronics. Computers, mobile phones, and other digital home appliances are now
inextricable parts of the structureof modern societies, made possibleby the low cost
of producing integrated circuits. Integrated Circuits (typically marked with an “U” or
“IC” on a circuit board)

7. RESULT :
We have observed various Electronic components which get commonly
used in electronic circuits with their different functions, specifications ,etc.
CONCLUSION :
We have studied about different electronic components
successfully.

8. Experiment No: 2
TITILE : Observe and draw V-I Characteristics of PN Diode & LED Diode.
AIM :
1. To observe and draw the Forward and Reverse bias V-I Characteristics of
a P-N Junction diode.
2.To study and measure the P-I characteristics of Light Emitting Diode
(LED), which used in optical fiber communication as a light source.
APPARATUS :
For P-N junction diode:
P-N Diode IN4007 2. Regulated Power supply (0-30V) 3. Resistor 1KΩ 4.
Ammeter (0-20 mA) 5. Ammeter (0-200µA) 6. Voltmeter (0-20V) 7. Bread
board 8. Connecting wires.
For LED:
1. Optical Fiber Communication Experiment Kit 2. Optical fiber power
meter 3. Oscilloscope 4. AVO meter 5. Wires 6. 5m multimode optical fiber
THOERY :
1. P-N junction diode:
Stucture of p-n junction diode:The diode is a device formed from a
junction of n-type & p-type semiconductors material.The lead
connected to the p-type material is called the anode and the lead
connected to the n-type material is the cathode.In,general,the
cathode of diodes is marked by a solid line on the diode.

9. A P-N junction diode conducts only in one direction. The V-I
characteristics of the diode are curve between voltage across the diode
and current flowing through the diode. When external voltage is zero,
circuit is open and the potential barrier does not allow the current to
flow. Therefore, the circuit current is zero. When P-type (Anode) is
connected to +ve terminal and n- type (cathode) is connected to –ve
terminal of the supply voltage is known as forward bias. The potential
barrier is reduced when diode is in the forward biased condition. At some
forward voltage, the potential barrier altogether eliminated and current
starts flowing through the diode and also in the circuit. Then diode is said
to be in ON state. The current increases with increasing forward voltage.
When N-type (cathode) is connected to +ve terminal and P-type (Anode)
is connected –ve terminal of the supply voltage is known as reverse bias
and the potential barrier across the junction increases. Therefore, the
junction resistance becomes very high and a very small current (reverse
saturation current) flows in the circuit. Then diode is said to be in OFF
state. The reverse bias current is due to minority charge carriers.

10. 2.For LED Diod: A Light Emitting Diode (LED) is a semiconductor diode that
emits light when an electric current is applied in forward direction of the
device as in simple LED circuit. The effect is a form of electroluminescence

11. where incoherent and narrow-spectrum light is emitted from the p-n
junction.
For optical communication systems requiring bit rates less than
approximately 100-200 Mb/s together with multimode fiber-coupled
optical power in tens of microwatts, semiconductor light-emitting diodes
(LEDs) are usually the best light source choice. LEDs require less complex
drive circuitry than laser diodes since no thermal or optical stabilization
circuits are needed and they can be fabricated less expensively with higher
yields.
To be useful in fiber transmission applications and LED must have a high
radiance output, a fast emission response time and high quantum
efficiency. To achieve a high radiance and a high quantum efficiency, the
LED structure must provide a means of confining the charge carriers and
the stimulated optical emission to the active region of the pn junction
where radiative recombination takes place.
The two basic LED configurations being used for fiber optics are surface
emitters and edge emitters.
Internal Quantum Efficiency
The internal quantum efficiency ηint is an important parameter of an LED. It
is defined as the fraction of the electron-hole pairs that recombine
radiatively. If the radiative recombination rate is Rr and the non-radiative
recombination rate isRnr, then the internal quantum efficiency is the ratio is
the ratio of the radaitive recombination rate to the total recombination
rate. ηint is typically 50% in homojunction LEDs, but ranges from 60 to 80%
in double-heterostructure LEDs.
Optical Power
If the current injected into the LED is I, then the total number of
recombinations per second is I/q, where q is the electron charge. Total
number of radaiative recombinations is equal to (ηint I/q). Since each
photon has an energy hν, the optical power generated internally by the LED
is: Pint = (ηint I/q)(hν).
External Quantum Efficiency

12. The external quantum efficiency (ηext)of a LED is defined as the ratio of the
photons emitted from the LED to the number of internally generated
photons. Due to reflection effects at the surface of the LED typical values
of ηout are < 10%.
LED Characteristics
Two important characteristics of a LED are its Light intensity vs. Current and
Junction Voltage vs. Current characteristics. These are described briefly
below.
i)Light Intensity (Optical Power) vs. Current
This is a very important characteristic of an LED. It was shown earlier that
the optical power generated by an LED is directly proportional to the
injected current I (current through the LED). However, in practice the
characteristic is generally non-linear, especially at higher currents. The
near-linear light output characteristic of an LED is exploited in small length
fiber optic analog communication links, such as fiber optic closed-circuit TV.
ii) Junction Voltage vs. Current
The junction voltage vs. current characteristic of an LED is similar to the V-I
characteristics of diodes. However, there is one major difference. The knee
voltage of a diode is related to the barrier potential of the material used in
the device. Silicon diodes and bipolar junction transistors are very
commonly used whose knee voltage or junction voltage is about 0.7 V. Very
often it is wrongly assumed that other diodes also have the same junction

13. voltage. In an LED, depending on the material used its junction voltage can
be anywhere between 1.5 to 2.2 Volts.
Light Dependent Resistor (LDR)
An electrical current consists of the movement of electrons within a
material. Good conductors have a large number of free electrons that can
drift in a given direction under the action of a potential difference.
Insulators with a high resistance have very few free electrons, and therefore
it is hard to make the them move and hence a current to flow.An LDR or
photoresistor is made any semiconductor material with a high resistance. It
has a high resistance because there are very few electrons that are free and
able to move - the vast majority of the electrons are locked into the crystal
lattice and unable to move. Therefore in this state there is a high LDR
resistance.As light falls on the semiconductor, the light photons are
absorbed by the semiconductor lattice and some of their energy is
transferred to the electrons. This gives some of them sufficient energy to
break free from the crystal lattice so that they can then conduct electricity.
This results in a lowering of the resistance of the semiconductor and hence
the overall LDR resistance. The process is progressive, and as more light
shines on the LDR semiconductor, so more electrons are released to
conduct electricity and the resistance falls further.
I-V Characteristics of LDR

14. PROCEDURE :
1. P-N junction diode:
A) FORWARD BIAS:
1. Connections are made as per the circuit diagram.
2. for forward bias, the RPS +ve is connected to the anode of the diode and
RPS –ve is connected to the cathode of the diode
3. Switch on the power supply and increases the input voltage (supply
voltage) in Steps of 0.1V 4. Note down the corresponding current flowing
through the diode and voltage across the diode for each and every step of
the input voltage.
5. The reading of voltage and current are tabulated.
6. Graph is plotted between voltage (Vf) on X-axis and current (If) on Y-axis.
2.For LED Diode:
1. Connect the circuit shown in Fig.(2) by using optical fiber trainer.
2. Connect the optical fiber to the LED.
3. Connected second end of optical fiber to the optical power meter.
4. Switch on optical fiber trainer.

15. 5. Change the injection current by varying the variable resistor in steps and
record the voltage of photo diode as in table below.
OBSERVATIONS:
A) FORWARD BIAS:
S.NO Forward Voltage(Vf) Forward Current(If(mA))
1. 0 0
2. 0.542 0.278
3. 0.552 0.834
4. 0.560 1.39
5. 0.567 2.09
B) REVERSE BIAS:
S.NO Reverse Voltage(VR) Reverse Current(IR(µA))
1. 0.0994 0
2. 0.288 0
3. 0.939 0
4. 1.88 0
5. 2.84 0

16. RESULT :
Plot the relationship between the optical output power and emitter current
CONCLUSION :
We studied about V-I Characteristics of PN Diode & LED Diode successfully.

17. Experiment No: 3
TITILE : Observe and draw the V-I characteristics and Regulation
characteristics of a Zener diode.
AIM : To observe and draw the V-I characteristics and Regulation
characteristics of a Zener diode.
APPARATUS::
1. Zener diode.
2. Regulated Power Supply (0-30v)
3. Voltmeter (0-20v).
4. Ammeter (0-20mA)
5. Resistor (1K ohm)
6. Bread Board
7. Connecting wires
THOERY :
Zener Diode
A Zener Diode is a special kind of diode which permits current to flow in
the forward direction as normal, but will also allow it to flow in the reverse
direction when the voltage is above the breakdown voltage or ‘zener’
voltage.
Zener diodes are designed so that their breakdown voltage is much lower
- for example just 2.4 Volts.
Function of Zener Diode:
1. Zener diodes are a special kind of diode which permits current to
flow in the forward direction.

18. 2. Zener diodes will also allow current to flow in the reverse direction
when the voltage is above a certain value. This breakdown voltage
is known as the Zener voltage. In a standard diode, the Zener
voltage is high, and the diode is permanently damaged if a reverse
current above that value is allowed to pass through it.
3. In the reverse bias direction, there is practically no reverse current
flow until the breakdown voltage is reached. When this occurs there
is a sharp increase in reverse current. Varying amount of reverse
current can pass through the diode without damaging it. The
breakdown voltage or zener voltage ((V_Z)) across the diode
remains relatively constant.
Zener Diode As A Voltage Regulator
A voltage regulator is an electronic circuit that provides a stable DC
voltage independent of the load current, temperature and AC line voltage
variations. A Zener diode of break down voltage (V_Z) is reverse
connected to an input voltage source (V_I) across a load resistance
(R_L) and a series resistor (R_S). The voltage across the zener will
remain steady at its break down voltage (V_Z) for all the values of zener
current (I_Z) as long as the current remains in the break down region.
Hence a regulated DC output voltage (V_0 = V_Z) is obtained across
(R_L), whenever the input voltage remains within a minimum and
maximum voltage. Basically there are two type of regulations such as:
Line Regulation: In this type of regulation, series resistance and load
resistance are fixed, only input voltage is changing. Output voltage
remains the same as long as the input voltage is maintained above a
minimum value.
Load Regulation: In this type of regulation, input voltage is fixed and the
load resistance is varying. Output volt remains same, as long as the load
resistance is maintained above a minimum value.
Line Regulation:

19. Load Regulation:
PROCEDURE :
Zener Diode - Line Regulation
1. Set the Zener Voltage(VZ)
2. Set the Series Resistance (RS) value.
3. Set the LoadResistance (RL) value.
4. Vary DC voltage.
5. Voltmeter is placed parallel to load resistor and ammeter series
with the series resistor.
6. Choose appropriate DC voltage such that zener diode is 'on'.
7. Now note the Voltmeter and Ammeter reading for various DC
voltage.
8. Note the Loadcurrent(IL), zener current(IZ), Output voltage(VO)
9. Calculate the voltage regulation.

20. 2.Zener Diode - LoadRegulation
1. Set DC voltage.
2. Set the Series Resistance (RS) value.
3. 1W D0-41 Glass Zener Diode 1N4740A, Zener voltage is 10 V.
4. Vary the LoadResistance (RL).
5. Voltmeter is placed parallel to load resistor and ammeter series with the
series resistor.
6. Choose LoadResistance in such a manner, such that the Zener diode is
'on'.
7. Now note the Voltmeter and Ammeter reading for various Load
Resistance.
8. Increase the load resistance (RL).
9. Note the Loadcurrent(IL), zener current(IZ), Output voltage(VO)
10.Calculate the voltage regulation.

21. 1.Zener Characteristics
1. Select the diode
2. Set the rheostat Rh=1 Ω
3. By adjusting the rheostat, voltmeter reading is increased from 0 and in
each time note the corresponding reading in milliammeter.
4. Take the readings and note Voltmeter reading across Zener diode and
Ammeter reading.
5. Plot the V-I graph and observe the change.
RESULT : We have observed and draw the V-I characteristics and
Regulation characteristics of a Zener diode.

22. CONCLUSION : We have observed and draw the V-I characteristics and
Regulation characteristics of a Zener diode successfully.

23. Experiment No: 4
TITLE: Design Clipper circuit using Diode.
AIM : To understand the theory of operation of the clipping diode
circuits.
• To design wave shapes that meet different circuit’s needs.
APPARATUS: one1µF capacitor , one 1kΩ resistor , one 22kΩ resistor ,
two 1N914 Diodes.
THEORY :
By definition, clipping circuits clip signals above a selected voltage level,
whereas clamping circuits shift the DC voltage of a waveform. Many wave
shapes can be produced with the proper application of these two
important diode functions.
1. Theoretical Output Voltages Predict the expected output waveform
of each circuit shown in Figures 1 through 6. Assume that the diodes
used in the circuit are ideal.
2. Clipping Circuit Design is a circuit to obtain an output waveform as
shown in Figure 7. Use a 1 kHz triangle wave with a 10-volt peak-to-
peak magnitude (zero DC offset) as the input signal.
PROCEDURE :
1. Clipping Circuit Form the circuit of Figure 1 on the breadboard. Display
both input and output on two separate DC coupled oscilloscope
channels. Observe and make scaled sketches of both input and output
waveforms. Use a 10 Volt peak-to-peak triangle wave with zero DC

24. offset at 1000 Hz as the input signal in this as well as all other
measurements of this experiment.
Replace the DC supply shown in Fig. 1 with a Zener diode as shown in Fig.
2. Measure the DC characteristic for the circuit.
• How will this characteristic change if both diodes reverse polarity?
• Apply a 10V peak-to-peak triangular waveform to the input and monitor
both input and output waveforms simultaneously. Capture the
oscilloscope display.
• Measure the clipping level of the waveform and compare it with the
measured DC characteristic. Comment on your finding!

25. Inverse
Clipping Circuit Form the circuit of Figure 3 on the breadboard. Repeat the
measurement by reversing the polarity of the diode used in the circuit of
Figure 1. Note that the white stripe on the black plastic diode corresponds
to the cathode (black line on the right-hand side of the diode symbol).
Display both input and output waveforms on two separate (dual channels)
DC coupled oscilloscope channels. Capture both input and output
waveforms on the same screen. Scale the drawing
Clipping with Zener diodes Measure the DC characteristic for the circuit
shown in Fig. 4 • Apply a 10V peak-to-peak triangular waveform and
capture both input and output waveforms on the same trace. • Measure
the clipping levels for the output waveforms and compare it with the
measured DC characteristic and the ratings of the Zener diodes. Comment
on your finding!

26. RESULT:
1. Error Analysis Perform an error analysis on the scaled sketches of the
preceding section. Compare the theoretical waveforms of the Prelab with
all of the experimentally measured waveforms. Calculate a percent error
for each of the key points of the output waveforms. The key points of the
output waveforms are the clip voltage levels.
2. Discussion Discuss the significance of the change in the output
waveform observed in Measurement # 7of the lab work for the two
values of RL used. Compare the theoretical output waveform to the
measured output waveform
CONCLUSION :
Hence, we conclude the Design of Clipper circuit using Diodes .

27. Experiment no: 5
TITLE :
To design the clamping circuit using diode.
AIM:
To design and simulate a clamper circuit Design.
APPARATUS:
Function generator, CRO, Regulated Power supply, resistor, diode,
connecting wires.
clamper circuit design has been implemented on the virtual breadboard
using following specifications:
· Power Supply: +10v and -10v
· Function generator: Selected wave with following specifications:
Frequency = 1KHz.
Amplitude: 5V
Duty cycle = 50%
· Resistor R1: 1.39K
THEORY:
Clamper is a circuit that "clamps" a signal to a different dc level. A clamping
network must have a capacitor, a diode and a resistive element. The
magnitude R and C must be chosen such that the time constant RC is large
enough to ensure that the voltage across the capacitor does not discharge
significantly during the interval the diode is non- conducting.
Positive Clamper
The circuit for a positive clamper is shown in the figure. During the negative
half cycle of the input signal, the diode conducts and acts like a short circuit.
The output voltage Vo = 0V. The capacitor is charged to the peak value of
input voltage Vm. and it behaves like a battery. During the positive half of
the input signal, the diode does not conduct and

28. PROCEDURE:
1. Connect the circuit as shown in the circuit diagram.
2. Give the input signal as specified.
3. Switch on the power supply.
4. Note down the value of AC and DC voltages from the CRO
5. Draw the necessary waveforms on the graph sheet.
OBSERVATIONS:
1. Observe the output waveform from CRO.
2. Measure the value of AC and DC voltages of the output and the input
waveforms from the CRO.
3. Observe and compare the maximum and minimum voltages of the
input and output waveforms.
VLab Observations Obtained:
From the Output waveform the following parameters has been observed
and tabulated down below:
Input Voltages Output VoltageMaximum0.23V2.72VMinimum-4.96V-2.59V
RESULT:
The Clamper circuit design output waveforms have been studied and the
required parameters has been compared.
Precautions:

29. 1. Connections should be verified before clicking run button.
2. The resistance to be chosen should be in K ohm range.
3. Best performance is being obtained within 50Hz to 1Mhz.
CONCLUSION :
Hence , we conclude the design of clipper Circuit using Diode

30. Experiment No: 6
TITLE : Obtain ripple factor of Half wave /Full Wave Rectifier circuit with &
Without Filter.
AIM: 1) To study the operation of half wave and full wave Rectifier
without filter .
To find it’s:
1. Ripple factor
APPARATUS:
Name Range Quantity
CRO (0-20) MHz 1
CRO probes 2
Digital ammeter,
voltmeter
(0-200A/200Ma, [0-20v] 1
Transformer 220v/9v,50Hz 1
Connecting wires
Specification:-
Silicon diode 1N4007:
Max’s forward current=1A
Max’s forward current=0.5 A
Max’s forward voltage=0.8 v
Max reverse voltage=1000V
Max power dissipation=30mW
Temperature=-65 to 200C
THEORY :A rectifier is circuit that converts a pure AC signal into pulsating
DC signal or a signal that is a combination of AC and DC components

31. A half wave rectifier makes use of single diode to carry out this conversion.it
is named so as the conversion occurs for half input signal cycle. During the
positive half cycle the diode is forward biased and it conducts and hence a
current flow through the load resistor. During the negative half cycle the
diode reverse biased and it is equivalent to the open circuit hence the
current through the load resistance is zero. Thus, the diode conducts only
for one half cycle and results in half wave rectified output.
A full wave rectifier makes use of two diodes to carry out this conversion .it
is named so as the conversion occurs for the complete input signal cycle.
The full wave rectifier consists of a centre -tap transformer ,which results in
equal voltages above and below centre tap during a positive half cycle ,a
positive half cycle a positive voltage appears at the anode of DI while
negative voltage appears at anode of D2. Due to this diode D1 is forward
biased it results in the current id1 through the load R . during the negative
half cycle ,a positive voltage appears at anode of D2 and hence it is forward
biased resulting in a current id2 through the load at the same instant a
negative voltage appears at the anode of D1 thus reverse biasing it and
hence it doesn’t conduct.
Circuit diagram:
Half wave rectifier(without filter):

32. Full wave rectifier (without filter)
PROCEDURE:
PART-I: Half wave rectifier without filter
1. Connect the circuit as shown in the fig.1.
2. Connect the multimeter across the 1kΩ load.
3. Measure the AC and DC voltages by setting multimeter to ac and dc
mode respectively.
4. Now calculate the ripple factor using the following formula.
Ripple factor (  ) = DC AC V
5. Connect the CRO channel-1 across input and channel-2 across output
i.e., load and Observe the input and output Waveforms.
6. Now calculate the peak voltage of input and output waveforms and also
the frequency
PART-II: Full wave rectifier without filter
1. Connect the circuit as shown in the fig.2

33. 2. Repeat the above steps 2-6
3. Plot different graphs for wave forms and calculate ripple factor
Results: 1. Half Wave and Full Wave rectifier characteristics are studied.
2. Ripple factor of Half wave rectifier founded .
3. Ripple factor of Full wave rectifier founded .
4. Regulation of Half wave rectifier founded .
5. Regulation of Full wave rectifier founded .
Conclusion : Hence , we conclude the obtain ripple factor of Half wave
/Full Wave Rectifier circuit with & Without Filter.

34. Experiment No: 7
TITILE : Draw the input and output characteristics of transistor connected
in CE/CB/CC any one Configuration.
AIM : To draw the input and output characteristics of transistor
connected in CE/CB/CC any one Configuration.
APPARATUS:
Transistor, BC107 -1No.
Regulated power supply (0-30V) -1No.
Voltmeter (0-20V) - 2No.
Ammeters (0-10mA) - 2No.
Resistor, 1KΩ - 2No
Bread board
Connecting wires
THEORY:
A transistor is a three terminal active device. The terminals are emitter,
base,collector. In CB configuration, the base is common to both input
(emitter) and output
(collector). For normal operation, the E-B junction is forward biased and C-
B junction
is reverse biased. In CB configuration, IE is +ve, IC is –ve and IB is –ve. So,
VEB = F1 (VCB, IE) and
IC = F2 (VEB,IB)
With an increasing the reverse collector voltage, the space-charge width at
the output
junction increases and the effective base width ‘W’ decreases. This
phenomenon is
known as “Early effect”. Then, there will be less chance for recombination
within the

35. base region.With increase of charge gradient with in the base region, the
current of
minority carriers injected across the emitter junction increases.
The current amplification factor of CB configuration is given by,
α = ΔIC/ ΔIE
Input Resistance, ri = ΔVBE /ΔIE at Constant VCB
Output Résistance, ro = ΔVCB /ΔIC at Constant IE
Circuit Digrams:
PROCEDURE :
A) INPUT CHARACTERISTICS:
1. Connections are made as per the circuit diagram.
2. For plotting the input characteristics, the output voltage VCE is kept
constant at 0V
and for different values of VEE note down the values of IE and VBE
3. Repeat the above step keeping VCB at 2V,4V,and 6V and all the readings
are
tabulated.
4. A graph is drawn between VEB and IE for constant VCB.

36. B) OUTPUT CHARACTERISTICS:
1. Connections are made as per the circuit diagram.
2. For plotting the output characteristics, the input IE is kept constant at
0.5mA and for
different values of VCC, note down the values of IC and VCB.
3. Repeat the above step for the values of IE at 1mA, 5mA and all the
readings are
tabulated.
4. A graph is drawn between VCB and Ic for constant IE.
RESULT :

37. Input and Output characteristics of a Transistor in Common Base
Configuration are studied.The h-parameters for a transistor in CB
configuration are:
The Input resistance (hib) Ohms.
The Reverse Voltage Transfer Ratio (hrb)
The Output Admittance (hob) Ohms.
The Forward Current gain (hfb)
CONCLUSION :
Students are able to,
Analyze the characteristics of BJT in Common Base Configuration.
Calculate h-parameters from the characteristics obtained.

38. Experiment No: 8
TITILE : Design bipolar junction transistor as a switch.
AIM : To design bipolar junction transistor as a switch.
APPARATUS:
ADALM1000 Hardware module
Solder-less Breadboard
1 - 6.8KΩ Resistor (RB)
1 - 100Ω Resistor (RC)
1 - 5mm LED (any color)
1 - small signal NPN transistor (2N3904)
THOERY : One common application for a BJT (or any other) switch is to
drive an LED. An LED driver is shown in figure 2. The driver shown in this
figure is used to couple a low current part of the circuit to a relatively high
current device (the LED). When the output from the low current circuit is
low (0 V), the transistor is in cutoff and the LED is off. When the output
from the low current circuit goes high (+3 V), the transistor is driven into
saturation and the LED lights. The driver is used because the low-current
part of the circuit may not have the current capability to supply the
20 mA (typical) required to light the LED to full brightness.
Build the LED switch circuit shown in figure 2 on your solder-less
breadboard. RC serves to limit the current that flows in the LED from the
+5 V power supply. The switch is controlled by the channel A voltage
output from the I/O connector. Scope channel B will display the voltage
across the switch transistor Q1 (VCE) or the voltage at the LED as indicated
by the green arrows.

39. Figure 2, NPN LED switch
Switches in Parallel:
Two NPN transistors can be connected with their collectors and emitters in
parallel, figure3, which provides a way to switch on the load from two
different signals. Either input can turn on the load but both need to be off
for the load to be off. This is referred to as an “OR” logic function.
Figure 3, Two Switches in parallel
Modify the circuit on your breadboard to look like figure 3. Add a second
NPN transistor, Q2, and second base resistor, RB2, as shown. Now connect
the other ends of RB1 and RB2 to the digital I/O port pins PIO 0 and PIO 1
respectively. Open the digital control window and set PIO 0 and PIO 1 to

40. all four combinations of logic 0 and 1. Note which combinations turn on
the LED. The voltage on the LED and collector resistor can be monitored
with the CHB scope input as before.
Switches in Series:
Two NPN transistors can be connected in series with the collector of the
lower transistor connected to the emitter of the upper transistor, figure 4,
which provides a way to switch off the load from two different signals.
Either input can turn off the load but both need to be on for the load to be
on. This is referred to as an “AND” logic function.
Figure 4, Two Switches in series
Modify the circuit on your breadboard to look like figure 4. Now the
second NPN transistor is in series with the emitter of Q1. Again, the other
ends of RB1 and RB2 are connected to the digital I/O port pins PIO 0 and PIO
1 respectively. Again, set PIO 0 and PIO 1 to all four combinations of logic 0
and 1. Note which combinations turn on the LED. The voltage on the LED
and collector resistor can be monitored with the CHB scope input as
before. You should also measure the voltage at the connection between
the emitter of Q1 and the collector of Q2 for each of the four conditions.
Comment on the voltages seen at the collector of Q2 in your lab report and
why.

41. BJT Transistor Realization of an XNOR gate
The single transistor inverter stage along with multiple input resistors can
be combined to create more complex logic functions. The configuration
shown in figure 5 realizes a two-input exclusive NOR (XNOR) logic function.
You will need a total of 5 NPN transistors, 13 resistors and one LED.
The resistors used as inputs at the bases of the 5 NPN transistors are not
all the same value and they in theory should all be the same value. But a
range of values will still work given the relatively high beta of the 2N3904
transistors and the values shown were chosen so as to not need more
than the 5 of any one value supplied in the Analog Parts Kit. You can
experiment with other resistor values to find what the range of minimum
and maximum values is.
Figure 5, Resistor and NPN transistor XNOR gate.
Again, set PIO 0 and PIO 1 to all four combinationsof logic 0 and
1. Note which combinationsturn on the LED. The voltage at the
LED and Q5 collectorresistor can be monitored with the CH-B
scope input as before. You can also use the CH-B ( and / or CH-A )
input to monitorthe voltages at the collectors of Q1 – Q4 as you
change PIO 0 and 1.

42. PROCEDURE: The CA generator should be configured for a 100 Hz
square wave with a 3-volt Max and 0-volt Min. Scope channel B is
connected to measure the voltage across the transistor or the at
the top of the LED. The current flowing through the transistor can
be calculatedas the voltage difference between the +5 V supply
and CB-V divided by the resistor value(100Ω). The ChannelA
current trace measures the current in RB.
Save the voltage trace across the transistor collector-emitter (
channelB dashed green line ) and at the LED ( channel B solid
green line ).
RESULT : We have design bipolarjunctiontransistor as a switch.
CONCLUSION : The design of bipolarjunctiontransistor as a
switch has been done successfully.

43. Experiment No: 9
TITILE : Draw the Drain and Transfer characteristics of a given FET in CS
Configuration.
AIM : To draw the Drain and Transfer characteristics of a given FET in CS
Configuration.
APPARATUS :
1-D.C power supply .
2-Oscilloscope ,A.V.Ometer .
3-FET, Resistors 1kΩ and 200kΩ.
THOERY : The acronym ‘FET’ stands for field effect transistor. It is a three-
terminal unipolar solidstate device in which current is controlled by an
electric field as is done in vacuum tubes. Broadly speaking, there are two
types of FETs :
(a) junction field effect transistor (JFET)
(b) metal-oxide semiconductor FET (MOSFET) It is also called insulated-
gate FET (IGFET).
It may be further subdivided into :
(i) depletion-enhancement MOSFET i.e., DEMOSFET
(ii) enhancement-only MOSFET i.e., E-only MOSFET Both of these can
be either P-channel or N-channel devices. The FET family tree is
shown below :

44. As shown in Fig.1, it can be fabricated with either an N-channel or P-
channel though N channel is generally preferred. For fabricating an N-
channel JFET, first a narrow bar of N type semiconductor material is taken
and then two P-type junctions are diffused on opposite sides of its middle
part [Fig.1 (a)]. These junctions form two P-N diodes or gates and the area
between these gates is called channel. The two P-regions are internally
connected and a single Electronics Laboratory lead is brought out which is
called gate terminal. Ohmic contacts (direct electrical connections) are
made at the two ends of the bar-one lead is called source terminal S and
the other drain terminal D. When potential difference is established
between drain and source, current flows along the length of the ‘bar’
through the channel located between the two P regions. The current
consists of only majority carriers which, in the present case, are electrons.
P-channel JFET is similar in construction except that it uses P-type bar and
two Ntype junctions. The majority carriers are holes which flow through
the channel located between the two N-regions or gates. Following FET
notation is worth remembering:
1. Source. It is the terminal through which majority carriers enter the bar.
Since carriers come from it, it is called the source.

45. 2. Drain. It is the terminal through which majority carriers leave the bar
i.e., they are drained out from this terminal. The drain to source voltage
VDS drives the drain current ID.
3. Gate. These are two internally-connected heavily-doped impurity
regions which form two P-N junctions. The gate-source voltage VGS
reverse biases the gates. 4. Channel. It is the space between two gates
through which majority carriers pass from source-to-drain when VDS is
applied. Schematic symbols for N-channel and P-channel JFET are shown in
Fig.1 (c). It must be kept in mind that gate arrow always points to N-type
material

46. c Characteristics of a JFET We will consider the following two
characteristics: (i) drain characteristic: It gives relation between ID and
VDS for different values of VGS (which is called running variable). (ii)
transfer characteristic: It gives relation between ID and VGS for different
values of VDS. We will analyze these characteristics for an N-channel JFET
connected in the common-source mode as shown in Fig. 2. We will first
consider the drain characteristic when VGS= 0 and then when VGS has any
negative value upto VGS(off).

47. JFET Drain Characteristic with VGS = 0
Such a characteristic is shown in Fig. 3. It can be subdivided into following
four regions :
1. Ohmic Region OA: This part of the characteristic is linear indicating that
for low values of VDS, current varies directly with voltage following Ohm's
Law. It means that JFET behaves like an ordinary resistor till point A (called
knee) is reached.
2. Curve AB In this region, ID increases at reverse square-law rate upto
point B which is called pinch-off point. This progressive decrease in the
rate of increase of ID is caused by the square law increase in the depletion
region at each gate upto point B where the two regions are closest
without touching each other.

48. 3. Pinch-off Region BC: It is also known as saturation region or ‘amplified’
region. Here, JFET operates as a constant-current device because ID is
relatively independent of VDS. It is due to the fact that as VDS increases,
channel resistance also increases proportionally thereby keeping ID
practically constant at IDSS. It should also be noted that the reverse bias
required by the gate-channel junction is supplied entirely by the voltage
drop across the channel resistance due to flow of IDSS and none by
external bias because VGS = 0. 4. Breakdown Region: If VDS is increased
beyond its value corresponding to point C (called avalanche breakdown
voltage), JFET enters the breakdown region where ID increases to an
excessive value. This happens because the reverse-biased gate-channel P-
N junction undergoes avalanche breakdown when small changes in VDS
produce very large changes in ID. It is interesting to note that increasing
values of VDS make a JFET behave first as a resistor (ohmic region), then as
a constant-current source (pinch-off region) and finally, as a
constantvoltage source (breakdown region).
PROCEDURE :

49. 1- Connect the circuit as shown in fig 4.
2- Let VDS =(0,0.5,1,1.5,2,2.5,3,4,5 )v measure ID.
3- Repeat step 3 for VGS =(0.5,1,1.5,2,2.5,3,3.5,4,4.5) V.
RESULT :
We have drawn the Drain and Transfer characteristics of a given FET in CS.
CONCLUSION :
We have drawn the Drain and Transfer characteristics of a given FET in CS
successfully

50. Experiment No: 10
TITILE : Draw the Drain and Transfer characteristics of a given MOSFET in
CS Configuration.
AIM : To draw the Drain and Transfer characteristics of a given MOSFET in
CS Configuration.
APPARATUS : MOSFET (2N7000), Bread board, resistor (1KΩ, 100KΩ),
connecting wires, Ammeters (0‐10mA/ 0‐25mA), DC power supply (0‐
30V) and multimeter.
CIRCUIT DIAGRAM:
THEORY:
MOSFET stands for Metal Oxide Silicon Field Effect Transistor or Metal
Oxide Semiconductor Field Effect Transistor. This is also called as IGFET
meaning Insulated Gate Field Effect Transistor. The FET is operated in both
depletion and enhancement modes of operation.

51. Construction of a MOSFET :
The construction of a MOSFET is a bit similar to the FET. An oxide layer is
deposited on the substrate to which the gate terminal is connected. This
oxide layer acts as an insulator (sio2 insulates from the substrate), and
hence the MOSFET has another name as IGFET. In the construction of
MOSFET, a lightly doped substrate, is diffused with a heavily doped region.
Depending upon the substrate used, they are called as P-type and N-type
MOSFETs.
The following figure shows the construction of a MOSFET :
The voltage at gate controls the operation of the MOSFET. In this case,
both positive and negative voltages can be applied on the gate as it is
insulated from the channel. With negative gate bias voltage, it acts as
depletion MOSFET while with positive gate bias voltage it acts as an
Enhancement MOSFET.
Classification of MOSFETs :
Depending upon the type of materials used in the construction, and the
type of operation, the MOSFETs are classified as in the following figure.

52. After the classification, let us go through the symbols of MOSFET.
The N-channel MOSFETs are simply called as NMOS. The symbols for N-
channel MOSFET are as given below.
The P-channel MOSFETs are simply called as PMOS. The symbols for P-
channel MOSFET are as given below.

53. Now, let us go through the constructional details of an N-channel MOSFET.
Usually, an NChannel MOSFET is considered for explanation as this one is
mostly used. Also, there is no need to mention that the study of one type
explains the other too.
Construction of N- Channel MOSFET :
Let us consider an N-channel MOSFET to understand its working. A lightly
doped P-type substrate is taken into which two heavily doped N-type
regions are diffused, which act as source and drain. Between these two N+
regions, there occurs diffusion to form an Nchannel, connecting drain and
source.
A thin layer of Silicon dioxide (SiO2) is grown over the entire surface and
holes are made to draw ohmic contacts for drain and source terminals. A
conducting layer of aluminum is laid over the entire channel, upon this
SiO2 layer from source to drain which constitutes the gate. The SiO2
substrate is connected to the common or ground terminals.
Because of its construction, the MOSFET has a very less chip area than BJT,
which is 5% of the occupancy when compared to bipolar junction

54. transistor. This device can be operated in modes. They are depletion and
enhancement modes. Let us try to get into the details.
Working of N - Channel depletionmode MOSFET :
For now, we have an idea that there is no PN junction present between
gate and channel in this, unlike a FET. We can also observe that, the
diffused channel N betweentwoN+regions, the insulating dielectric SiO2
and the aluminum metal layer of the gate together form a parallel plate
capacitor.
If the NMOS has to be worked in depletion mode, the gate terminal should
be at negative potential while drain is at positive potential, as shown in
the following figure.
When no voltage is applied between gate and source, some current flows
due to the voltage between drain and source. Let some negative voltage is
applied at VGG. Then the minority carriers i.e., holes, get attracted and
settle near SiO2 layer. But the majority carriers, i.e., electrons get repelled.

55. With some amount of negative potential at VGG a certain amount of drain
current ID flows through source to drain. When this negative potential is
further increased, the electrons get depleted and the current ID decreases.
Hence the more negative the applied VGG, the lesser the value of drain
current ID will be.
he channels nearer to drain gets more depleted than at source likeinFET
and the current flow decreases due to this effect. Hence it is called as
depletion mode MOSFET.
Working of N-Channel MOSFET EnhancementMode :
The same MOSFET can be worked in enhancement mode, if we can change
the polarities of the voltage VGG. So, let us consider the MOSFET with gate
source voltage VGG being positive as shown in the following figure

56. When no voltage is applied between gate and source, some current flows
due to the voltage between drain and source. Let some positive voltage is
applied at VGG. Then the minority carriers i.e., holes, get repelled and the
majority carriers i.e., electrons get attracted towards the SiO2 layer.
With some amount of positive potential at VGG a certain amount of drain
current ID flows through source to drain. When this positive potential is
further increased, the current ID increases due to the flow of electrons
from source and these are pushed further due to the voltage applied at
VGG. Hence the more positive the applied VGG, the more the value of
drain current ID will be. The current flow gets enhanced due to the
increase in electron flow better than in depletion mode. Hence this mode
is termed as Enhanced Mode MOSFET.
P - Channel MOSFET :

57. The construction and working of a PMOS is same as NMOS. A lightly doped
n-substrate is taken into which two heavily doped P+ regions are diffused.
These two P+ regions act as source and drain. A thin layer of SiO2 is grown
over the surface. Holes are cut through this layer to make contacts with P+
regions, as shown in the following figure.
Working of PMOS
When the gate terminal is given a negative potential at VGG than the drain
source voltage VDD, then due to the P+ regions present, the hole current
is increased through the diffused P channel and the PMOS works in
Enhancement Mode.
When the gate terminal is given a positive potential at VGG than the drain
source voltage VDD, then due to the repulsion, the depletion occurs due
to which the flow of current reduces. Thus, PMOS works in Depletion
Mode. Though the construction differs, the working is similar in both the
type of MOSFETs. Hence with the change in voltage polarity both of the
types can be used in both the modes.
This can be better understood by having an idea on the drain
characteristics curve

58. PROCEDURE:
OUTPUT/DRAINCHARACTERISTICS:
1. Connect the circuit as per given diagram properly.

59. 2. KeepVGSconstant at some value say 1.1 Vby varying VGG
3. Vary VDSin step of 1V up to 10 volts and measure the drain current
ID.Tabulate all the readings.
4. Repeat the above procedure forVGSas 1.2V, 1.3V, 1.4V, 1.5Vetc
TRANSFER CHARACTERISTICS:
1. Connect the circuitas per given diagram properly.
2. Set the voltage VDSconstant at 10 V.
3. Vary VGSby varying VGGin the step of 0.1up to 1.55V and note down
value of drain current ID. Tabulate all the readings.
4. Plot the output characteristics VDSvs IDand transfer characteristics
VGSvs ID.
5. Calculate VT, gm, rd or rofrom the graphs and verify it from the data
sheet
CALCULATION:
1.Threshold voltageVT: Gate to source voltage at which, drain current
starts flowing.
2.Transconductance gm : Ratio of small change in drain current (Δ ID) to
the corresponding change in gate to source voltage (ΔVGS) for a constant
VDS
gm= Δ ID/ ΔVGSat constant VDS

60. 3.Output drain resistance : It is given by the relation of small change in
drain to source voltage(Δ VDS) to the corresponding change in Drain
Current(ΔID) for a constant VGS.
rdor ro = ΔVDS/ Δ IDat a constant VGS
CONCLUSION:
The drain and transfer characteristics of a given MOSFET are drawn.