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Short Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and Fabrication
Jointly Organized by: Dept. of EEE and IEEE RUET
Lecture 1: Resistor Capacitor, Induction, Transformer, Diode
Problem 1: Design a DC Power Supply.
Solve: You can make a DC power Supply from the following Circuit.
If it is 7805, then it is +5V Voltage regulator, if it is 7809, then it is +9V voltage regulator. On the other hand if it is 790
then it is -5V voltage regulator, if it is 7909 then it is
Here, S1 – Switch, 3A – 3A Fuse, T1 - Transformer,
microfarad. You can also use different transformer, such as 220V/12V transformer.
Abdullah Al Bashit
Color Coding of Resistor:
Black Brown Red Orange Yellow
0 1 2 3 4
Resistance = (1st
Band|2nd
Band)*103rd Band
± Tolerance
Details of Color coding, Tolerance, Resistor Power
Thermistor, LDR, Varistor etc with example will be
Application of Resistor:
Lightbulb
There is nothing special about a lightbulb filament
metallic gum wrapper and connecting the wrapper across the terminals of a 9
instantly burn out. Edison solved this technical challenge by encasing the filament in an evacuated bulb, which
prevented burning, since burning requires oxygen
Fuse
A fuse is a device inserted in a circuit tollbooth
made of metals having a relatively low melting point. If too much current passes through the fuse, it melts, opening the
circuit. The purpose is to make sure that the building's wires do not carry so much current that they themselves will get
hot enough to start a fire. Most modern houses use circuit breakers instead of fuses, although fuses are still common in
Editor: MD. Mahbub H
Short Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and Fabrication
Jointly Organized by: Dept. of EEE and IEEE RUET Student Branch
Lecture 1: Resistor Capacitor, Induction, Transformer, Diode, Relay, Project Board, Multimeter
You can make a DC power Supply from the following Circuit. In the figure LM78XX, XX means 05,09,12 etc.
it is 7805, then it is +5V Voltage regulator, if it is 7809, then it is +9V voltage regulator. On the other hand if it is 790
5V voltage regulator, if it is 7909 then it is -9V voltage regulator IC.
sformer, D – Diode, C – Capacitor, LM78XX – Voltage regulator IC.
You can also use different transformer, such as 220V/12V transformer.
Resistor Abdullah Al Bashit, EEE-061048, RUET. email: [email protected]
Yellow Green Blue Violate Gray White Gold
5 6 7 8 9 5%
± Tolerance
olerance, Resistor Power rating, Resistor types, Series Parallel combination of
etc with example will be explained in the class lecture.
There is nothing special about a lightbulb filament - you can easily make a lightbulb by cutting a narrow wa
metallic gum wrapper and connecting the wrapper across the terminals of a 9-volt battery. The trouble is that it will
instantly burn out. Edison solved this technical challenge by encasing the filament in an evacuated bulb, which
oxygen.
A fuse is a device inserted in a circuit tollbooth-style in the same manner as an ammeter. It is simply a piece of wire
latively low melting point. If too much current passes through the fuse, it melts, opening the
circuit. The purpose is to make sure that the building's wires do not carry so much current that they themselves will get
houses use circuit breakers instead of fuses, although fuses are still common in
D
C
Hasan, EEE-061017 & Tanvir Hussain, EEE-061049, RU
1
, Relay, Project Board, Multimeter
In the figure LM78XX, XX means 05,09,12 etc.
it is 7805, then it is +5V Voltage regulator, if it is 7809, then it is +9V voltage regulator. On the other hand if it is 7905
Voltage regulator IC. uF means
Silver None
10% 20%
el combination of Resistors,
you can easily make a lightbulb by cutting a narrow waist into a
volt battery. The trouble is that it will
instantly burn out. Edison solved this technical challenge by encasing the filament in an evacuated bulb, which
style in the same manner as an ammeter. It is simply a piece of wire
latively low melting point. If too much current passes through the fuse, it melts, opening the
circuit. The purpose is to make sure that the building's wires do not carry so much current that they themselves will get
houses use circuit breakers instead of fuses, although fuses are still common in
UET
Short Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and Fabrication
Jointly Organized by: Dept. of EEE and IEEE RUET
cars and small devices. A circuit breaker is a switch operated by a coiled
enough current flows. The advantage is that once you turn
current, you can immediately flip the switch closed. In the days of fuses, one might get caught without a replacement
fuse, or even be tempted to stuff aluminum
Voltmeter
A voltmeter is nothing more than an ammeter with an additional high
forced to flow.
Polygraph
The polygraph, or "lie detector," is really just a set of meters for recording physical measures of the subject's
psychological stress, such as sweating and quickened heartbeat. The real
principle that dry skin is a good insulator,
nervous simply because of the situation, and a practiced liar may not even break a sweat.
Heater
In Home we use room heater, oven etc. These devices
Details of Capacitor voltage rating, Series parallel connection, types,
etc. will be explained in the class.
Application of Capacitor:
Energy storage
A capacitor can store electric energy when disconnected from its charging circuit, so it can be used like a temporary
battery. Capacitors are commonly used in elect
(This prevents loss of information in volatile memory.)
Pulsed power and weapons
Groups of large, specially constructed, low-
pulses of current for many pulsed power applications. These include
lasers (especially TEA lasers), pulse forming networks
Large capacitor banks(Reservoir) are used as energy sources for the
detonators in nuclear weapons and other specialty weapons. Experimental work is under way using banks of capacitors as
power sources for electromagnetic armor and electromagnetic
Power conditioning
Reservoir capacitors are used in power supplies
also be used in charge pump circuits as the energy storage element in the generation of higher voltages than the input
voltage (such as stun gun). Capacitors are connected in parallel with the power circuits of most electronic devices and
larger systems (such as factories) to shunt away and conceal current fluctuations from the primary power source to
Abu Sadat Saym
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cars and small devices. A circuit breaker is a switch operated by a coiled-wire magnet, which opens the circuit when
enough current flows. The advantage is that once you turn off some of the appliances that were sucking up too much
current, you can immediately flip the switch closed. In the days of fuses, one might get caught without a replacement
aluminum foil in as a replacement, defeating the safety feature.
A voltmeter is nothing more than an ammeter with an additional high-value resistor through which the current is also
h, or "lie detector," is really just a set of meters for recording physical measures of the subject's
psychological stress, such as sweating and quickened heartbeat. The real-time sweat measurement works on the
principle that dry skin is a good insulator, but sweaty skin is a conductor. Of course a truthful subject may become
nervous simply because of the situation, and a practiced liar may not even break a sweat.
In Home we use room heater, oven etc. These devices produce heat from a resistor through which high current flows.
Capacitor
Details of Capacitor voltage rating, Series parallel connection, types, energy stored in the capacitor, charging, discharging
pacitor can store electric energy when disconnected from its charging circuit, so it can be used like a temporary
. Capacitors are commonly used in electronic devices to maintain power supply while batteries are being changed.
(This prevents loss of information in volatile memory.)
-inductance high-voltage capacitors (capacitor banks
applications. These include electromagnetic forming
pulse forming networks, radar, fusion research, and particle accelerators
servoir) are used as energy sources for the exploding-bridge wire detonators
and other specialty weapons. Experimental work is under way using banks of capacitors as
and electromagnetic railguns or coilguns.
power supplies where they smooth the output of a full or half wave
circuits as the energy storage element in the generation of higher voltages than the input
Capacitors are connected in parallel with the power circuits of most electronic devices and
systems (such as factories) to shunt away and conceal current fluctuations from the primary power source to
Capacitance = (1st Code|2
nd Code)*10^3
rd
Capacitance of the above mica capacitor
Abu Sadat Saym, EEE-061001, RUET
2
wire magnet, which opens the circuit when
off some of the appliances that were sucking up too much
current, you can immediately flip the switch closed. In the days of fuses, one might get caught without a replacement
as a replacement, defeating the safety feature.
value resistor through which the current is also
h, or "lie detector," is really just a set of meters for recording physical measures of the subject's
time sweat measurement works on the
but sweaty skin is a conductor. Of course a truthful subject may become
h which high current flows.
energy stored in the capacitor, charging, discharging
pacitor can store electric energy when disconnected from its charging circuit, so it can be used like a temporary
ronic devices to maintain power supply while batteries are being changed.
capacitor banks) are used to supply huge
electromagnetic forming, Marx generators, pulsed
particle accelerators.
wire detonators or slapper
and other specialty weapons. Experimental work is under way using banks of capacitors as
where they smooth the output of a full or half wave rectifier. They can
circuits as the energy storage element in the generation of higher voltages than the input
Capacitors are connected in parallel with the power circuits of most electronic devices and
systems (such as factories) to shunt away and conceal current fluctuations from the primary power source to
rd Code ± Tolerance pF
capacitor is 10*10^4±10% pF
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provide a "clean" power supply for signal or control circuits. Audio equipment, for example, uses several capacitors in
this way, to shunt away power line hum before it gets into the signal circuitry.
Power factor correction
In electric power distribution, capacitors are used for power factor correction.
Signal coupling
Because capacitors pass AC but block DC signals (when charged up to the applied dc voltage), they are often used to
separate the AC and DC components of a signal. This method is known as AC coupling or "capacitive coupling".
Decoupling
A decoupling capacitor is a capacitor used to decouple one part of a circuit from another. Noise caused by other circuit
elements is shunted through the capacitor, reducing the effect they have on the rest of the circuit. It is most commonly
used between the power supply and ground. An alternative name is bypass capacitor as it is used to bypass the power
supply or other high impedance component of a circuit.
Noise filters and snubbers
When an inductive circuit is opened, the current through the inductance collapses quickly, creating a large voltage across
the open circuit of the switch or relay. If the inductance is large enough, the energy will generate a spark, causing the
contact points to oxidize, deteriorate, or sometimes weld together, or destroying a solid-state switch. A snubber capacitor
across the newly opened circuit creates a path for this impulse to bypass the contact points, thereby preserving their life;
these were commonly found in contact breaker ignition systems, for instance. Similarly, in smaller scale circuits, the spark
may not be enough to damage the switch but will still radiate undesirable radio frequency interference (RFI), which a
filter capacitor absorbs. Snubber capacitors are usually employed with a low-value resistor in series, to dissipate energy
and minimize RFI. Such resistor-capacitor combinations are available in a single package.
Motor starters
In single phase squirrel cage motors, the primary winding within the motor housing isn't capable of starting a rotational
motion on the rotor, but is capable of sustaining one. To start the motor, a secondary winding is used in series with a non-
polarized starting capacitor to introduce a lag in the sinusoidal current through the starting winding. When the secondary
winding is placed at an angle with respect to the primary winding, a rotating electric field is created. The force of the
rotational field is not constant, but is sufficient to start the rotor spinning.
Signal processing
The energy stored in a capacitor can be used to represent information, either in binary form, as in DRAMs, or in analogue
form, as in analog sampled filters and CCDs. Capacitors can be used in analog circuits as components of integrators or
more complex filters and in negative feedback loop stabilization. Signal processing circuits also use capacitors to integrate
a current signal.
Sensing
Most capacitors are designed to maintain a fixed physical structure. However, various factors can change the structure of
the capacitor; the resulting change in capacitance can be used to sense those factors.
Changing the dielectric:
The effects of varying the physical and/or electrical characteristics of the dielectric can also be of use. Capacitors with an
exposed and porous dielectric can be used to measure humidity in air. Capacitors are used to accurately measure the fuel
level in airplanes; as the fuel covers more of a pair of plates, the circuit capacitance increases.
Changing the distance between the plates:
Capacitors with a flexible plate can be used to measure strain or pressure. Industrial pressure transmitters used for process
control use pressure-sensing diagphragms, which form a capacitor plate of an oscillator circuit. Capacitors are used as the
sensor in condenser microphones, where one plate is moved by air pressure, relative to the fixed position of the other
plate. Some accelerometers use MEMS capacitors etched on a chip to measure the magnitude and direction of the
acceleration vector. They are used to detect changes in acceleration, eg. as tilt sensors or to detect free fall, as sensors
triggering airbag deployment, and in many other applications. Some fingerprint sensors use capacitors. Additionally, a
user can adjust the pitch of a theremin musical instrument by moving his hand since this changes the effective capacitance
between the user's hand and the antenna.
Changing the effective area of the plates:
Capacitive touch switches are now used on many consumer electronic products.
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Diode Md. Abdul Motin, EEE-061005, RUET
Some elements are linear (resistors, capacitors, inductors), which means that doubling the applied signal (let us say a
voltage) produces a doubling of the response (let us say a current). They are also passive – they do not have built-in
source of power. They are two-terminal devices, (which is self-explanatory). Diode is also two-terminal, passive but non-
linear a device. Figure 1 shows the diode.
Fig.1. Diode. Fig.2. Diode voltage-current curve, U-I curve.
In Fig. 2 there is U-I (voltage-current) curve (characteristic). The diode arrow, anode terminal, shows the direction of
forward current flow. If the diode is in a circuit in which a current of 10mA=10*10-3
A is flowing from anode to cathode,
then the anode is approximately 0.5 volt more positive than cathode. We call it the forward voltage drop. The reverse
current is measured in nano ampers and 1nA=1*10-9
A. It is so small in comparison to mA, that can be neglected until we
reach the reverse breakdown voltage. Typically it is approximately 75V and normally we never subject a diode to voltage
large enough to cause reverse breakdown. Similarly, the forward voltage drop, which is about 0.5 or 0.8 V, is of little
concern. For these reasons we treat the diode as a good approximation of an ideal one-way conductor.
Commercially available diodes are described also by other important characteristics, e.g.: maximum forward current,
capacitance (measured in pF), leaking current, reverse recovery time (measured in nanoseconds, 0-2-4-5000).
Rectification
A rectifier changes ac (alternating current) to dc (direct current). This is the most important application of diodes. Diodes
are sometimes called rectifiers.
The basic circuit is shown in Fig. 3.
Fig.3. Half-wave rectifier.
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The ac represents a source of ac voltage. It can be a
amplitude much larger than forward voltage drop, the output will look like it is shown in Fig. 4.
The process and the circuit we call a half-wave
shown a full-wave rectifier and Fig. 6 shows the voltage across the load. The small gaps across zero voltage occur
because of the forward voltage drop.
Fig.5. Full-wave bridge rectifier.
Power supply filtering
The rectified wave from Fig.6 is not good for application: it is dc only in the sense that it does not change polarity. But i
does not have constant value and has plenty of ripples i
smoothed out in order to obtained authentic direct current. This can be done by means of a low
in Fig. 7.
The full-wave bridge diodes prevent flow of current back out of capacitor. The capacitor is an energy storage element.
The energy stored in a capacitor is 2
1CUE =
J=Watt/sek. The capacitor value is chosen so that
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The ac represents a source of ac voltage. It can be a transformer or just ac sine-wave power line. For sine
amplitude much larger than forward voltage drop, the output will look like it is shown in Fig. 4.
Fig.4. Voltage across Rload in Fig.3.
wave rectifier, because only half of the input waveform is used. In Fig. 5 is
and Fig. 6 shows the voltage across the load. The small gaps across zero voltage occur
Fig.6. Voltage across Rload in Fig.5.
The rectified wave from Fig.6 is not good for application: it is dc only in the sense that it does not change polarity. But i
does not have constant value and has plenty of ripples i.e. small waves or undulations (wave like forms). It has to be
smoothed out in order to obtained authentic direct current. This can be done by means of a low-
Fig.7. Full-wave bridge with RC filter.
idge diodes prevent flow of current back out of capacitor. The capacitor is an energy storage element.
2CU . For C in F (farads) and U in V (Volts), E comes out in J (jouls) and
or value is chosen so that f/R load 1>> , where f is the ripple frequency. For power line sine wave
5
wave power line. For sine-wave input, of
amplitude much larger than forward voltage drop, the output will look like it is shown in Fig. 4.
, because only half of the input waveform is used. In Fig. 5 is
and Fig. 6 shows the voltage across the load. The small gaps across zero voltage occur
The rectified wave from Fig.6 is not good for application: it is dc only in the sense that it does not change polarity. But it
.e. small waves or undulations (wave like forms). It has to be
-pass filter, which is shown
idge diodes prevent flow of current back out of capacitor. The capacitor is an energy storage element.
. For C in F (farads) and U in V (Volts), E comes out in J (jouls) and
, where f is the ripple frequency. For power line sine wave
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it is 2*50Hz=100Hz. It allows to ensure small ripples, by making the time constant for discharge much longer than the
time between recharging (the capacitor is charging very quickly, while discharging is very slow).
It is quite easy to calculate the approximate ripple voltage (see Fig. 8). Let us assume that the load current stays constant
(it will, for small ripples). The load causes the capacitor to discharge somewhat between cycles. The capacitor will loose
some voltage, let us say U∆ . In this case, we have:
tC
IU ∆=∆ , (from
dt
dUCI = )
Fig.8. Power-supply ripple calculation.
Instead of t∆ we use f/1 or f/ 21 respectively for half-wave rectification and for full-wave rectification. Finally we
obtain approximate ripple voltage:
° for halve-wave fC
IU load=∆ ,
° for full-wave fC
IU load
2=∆ .
If one wanted to do exact calculation (with no approximation), one would use the exact exponential formula (see lecture
Capacitors, RC circuits). Sometimes it may be necessary. A dc power supply using the bridge circuit looks (in the USA)
as shown in Fig.9.
Fig.9. Bridge rectifier circuit. The curved electrode indicates a polarized capacitor, which must not be allowed the
opposite polarity.
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Application of Diode:
Signal rectifier
If the input is not a sine wave, we usually do not think of it as a rectification in the sense as it was for power supply. For
instance, we might want to have a series of pulses corresponding to the rising edge of a square wave (see Figure, left hand
side and right hand side of the capacitor C). While both, the rising and the falling, pulses are in the output after
differentiation performed by CR circuit. The simplest way is to rectify the differentiated wave.
Figure: A series of pulses' rectifier.
We should remember about forward drop voltage of the diode: This circuit gives no output for signal for input smaller
then, forward drop voltage, let us say 0.5 V pp (peak to peak). If this is a problem, there are various tricks that help to
combat this limitation. For instance:
• use Schottky diodes with smaller forward drop voltage (approximately 0.2V),
• use so called circuit solution, which means modifying the circuit structure and compensating the drop,
• use matched-pair compensation, use transistors, FETs.
Diode gates
Another application of diode is to pass the higher of two voltages without affecting the lower. A good example is battery
backup, a method of keeping s device running (for instance a precision electronic clock) in case of power failure. Figure
shows a circuit that does the job.
Figure: Diode OR gate, battery backup.
[OR gate: The output of OR gate is HIGH if either input (or both) is HIGH. In general, gates can have any number of
inputs. The output is LOW only if all inputs are LOW].
The battery does nothing until the power fails. Then the battery takes over the control, without interruption.
Diode clamps
Sometimes it is necessary to limit the range of signal (for instance not to exceed certain voltage limit and not to destroy a
device). The circuit in Figure will accomplish this.
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The diode prevents the output from exceeding
voltages. The only limitation is that the input must not be so negative that the reverse breakdown v
Diode clamps are the standard equipment on all inputs in the CMOS family of digital logic (Complementary Metal Oxide
Semiconductor). Without them, the delicate input circuits are easily destroyed by static electricity.
Limiter
The circuit in Figure limits the output swing
Fig
It might seem very small, but if the next device is an amplifier with large voltage amplification, its input has to be always
near zero voltage. Otherwise the output is in state of saturation. For instance we have an op amp with a gain of 1000. The
amplifier operates with supply voltage ±15V. Sometimes it can be
give output voltage bigger than the supply voltag
will saturate the output. This particular amplifier gives the output proportional to the input (proportionality factor is 100
only for input signals from the interval (-15mV,+15mV).
amplifiers.
Details of clippers, clampers, voltage multiplier, series parallel configuration of diode, zener diode will be explained in t
class.
Application of Relay:
• Control a high-voltage circuit with a low
audio amplifiers
• Control a high-Current circuit with a low
automobile
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Figure: Diode voltage clamp.
The diode prevents the output from exceeding ≅ 5.6V, with no effect on voltages smaller than this, including negative
voltages. The only limitation is that the input must not be so negative that the reverse breakdown v
Diode clamps are the standard equipment on all inputs in the CMOS family of digital logic (Complementary Metal Oxide
Semiconductor). Without them, the delicate input circuits are easily destroyed by static electricity.
output swing to one diode drop, roughly 0.6V.
Figure: Diode limiter.
It might seem very small, but if the next device is an amplifier with large voltage amplification, its input has to be always
output is in state of saturation. For instance we have an op amp with a gain of 1000. The
15V. Sometimes it can be ±12V or ±18V or something in between. It will never
give output voltage bigger than the supply voltage, i.e. ±15V. It means that the input signal ±15mV (
will saturate the output. This particular amplifier gives the output proportional to the input (proportionality factor is 100
15mV,+15mV). This diode limiter is often used as input protection for high
Details of clippers, clampers, voltage multiplier, series parallel configuration of diode, zener diode will be explained in t
Relay Anisur Rahman, EEE-061016, RUET
voltage circuit with a low-voltage signal, as in some types of modems or
Current circuit with a low-current signal, as in the starter solenoid of an
8
5.6V, with no effect on voltages smaller than this, including negative
voltages. The only limitation is that the input must not be so negative that the reverse breakdown voltage is exceeded.
Diode clamps are the standard equipment on all inputs in the CMOS family of digital logic (Complementary Metal Oxide
Semiconductor). Without them, the delicate input circuits are easily destroyed by static electricity.
It might seem very small, but if the next device is an amplifier with large voltage amplification, its input has to be always
output is in state of saturation. For instance we have an op amp with a gain of 1000. The
18V or something in between. It will never
15mV (±15V/1000) or bigger
will saturate the output. This particular amplifier gives the output proportional to the input (proportionality factor is 1000)
This diode limiter is often used as input protection for high-gain
Details of clippers, clampers, voltage multiplier, series parallel configuration of diode, zener diode will be explained in the
or
of an
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• Detect and isolate faults on transmission and distribution lines by opening
and closing circuit breakers (protection relays)
• Isolate the controlling circuit from the controlled circuit when the two are at
different potentials, for example when controlling a mains-powered device
from a low-voltage switch. The latter is often applied to control office
lighting as the low voltage wires are easily installed in partitions, which may
be often moved as needs change. They may also be controlled by room
occupancy detectors in an effort to conserve energy,
• Logic functions. For example, the boolean AND function is realised by connecting normally open relay contacts
in series, the OR function by connecting normally open contacts in parallel. The change-over or Form C contacts
perform the XOR (exclusive or) function. Similar functions for NAND and NOR are accomplished using
normally closed contacts. The Ladder programming language is often used for designing relay logic networks.
• Early computing. Before vacuum tubes and transistors, relays were used as logical elements in digital computers.
See ARRA (computer), Harvard Mark II, Zuse Z2, and Zuse Z3.
• Safety-critical logic. Because relays are much more resistant than semiconductors to nuclear radiation, they are
widely used in safety-critical logic, such as the control panels of radioactive waste-handling machinery.
• Time delay functions. Relays can be modified to delay opening or delay closing a set of contacts. A very short (a
fraction of a second) delay would use a copper disk between the armature and moving blade assembly. Current
flowing in the disk maintains magnetic field for a short time, lengthening release time. For a slightly longer (up to
a minute) delay, a dashpot is used. A dashpot is a piston filled with fluid that is allowed to escape slowly. The
time period can be varied by increasing or decreasing the flow rate. For longer time periods, a mechanical
clockwork timer is installed.
Transformer Jewel, EEE, RUET
Application of Transformer:
• A major application of transformers is to increase voltage
before transmitting electrical energy over long distances
through wires. Wires have resistance and so dissipate
electrical energy at a rate proportional to the square of the
current through the wire. By transforming electrical power to
a high-voltage (and therefore low-current) form for
transmission and back again afterward, transformers enable
economic transmission of power over long distances.
• Transformers are also used extensively in electronic products
to step down the supply voltage to a level suitable for the low
voltage circuits they contain. The transformer also electrically
isolates the end user from contact with the supply voltage.
• Signal and audio transformers are used to couple stages of
amplifiers and to match devices such as microphones and
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record players to the input of amplifiers. When this is done to improve power transfer to a load, it is called
impedance matching. Audio transformers allowed telephone circuits to carry on a two-way conversation over a
single pair of wires.
• A Potential Transformer (PT) is a special instrument transformer designed to provide a precise voltage step-
down ratio for voltmeters measuring high power system voltages.
• A Current Transformer (CT) is another special instrument transformer designed to step down the current
through a power line to a safe level for an ammeter to measure.
• A Tesla Coil is a resonant, air-core, step-up transformer designed to produce very high AC voltages at high
frequency.
• A Scott-T transformer converts 3-φ power to 2-φ power and vice versa.
• A linear variable differential transformer, also known as an LVDT, is a distance measuring device. It has a
movable ferromagnetic core to vary the coupling between the excited primary and a pair of secondary’s.
Inductor Nura Alam, EEE-061050, RUET
Application of Inductor:
• Inductors are used extensively in analog circuits and signal processing. Inductors in conjunction with capacitors
and other components form tuned circuits which can emphasize or filter out specific signal frequencies.
Applications range from the use of large inductors in power supplies, which in conjunction with filter capacitors
remove residual hums known as the Mains hum or other fluctuations from the direct current output, to the small
inductance of the ferrite bead or torus installed around a cable to prevent radio frequency interference from being
transmitted down the wire. Smaller inductor/capacitor combinations provide tuned circuits used in radio reception
and broadcasting, for instance.
• Two (or more) inductors which have coupled magnetic flux form a transformer, which is a fundamental
component of every electric utility power grid. The efficiency of a transformer may decrease as the frequency
increases due to eddy currents in the core material and skin effect on the windings. Size of the core can be
decreased at higher frequencies and, for this reason, aircraft use 400 hertz alternating current rather than the usual
50 or 60 hertz, allowing a great saving in weight from the use of smaller transformers.
• An inductor is used as the energy storage device in some switched-mode power supplies. The inductor is
energized for a specific fraction of the regulator's switching frequency, and de-energized for the remainder of the
cycle. This energy transfer ratio determines the input-voltage to output-voltage ratio. This XL is used in
complement with an active semiconductor device to maintain very accurate voltage control.
• Inductors are also employed in electrical transmission systems, where they are used to depress voltages from
lightning strikes and to limit switching currents and fault current. In this field, they are more commonly referred
to as reactors.
Multimeter Mahbub, EEE-061017, RUET
Application of multimeter:
Contemporary multimeters can measure many quantities. The common ones are:
• Voltage in volts.
• Current in amperes.
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• Resistance in ohms.
Additionally, multimeters may also measure:
• Capacitance in farads.
• Conductance in siemens.
• Decibels.
• Duty cycle as a percentage.
• Frequency in hertz
• Inductance in henrys
• Temperature in degrees Celsius or Fahrenheit
Digital multimeters may also include circuits for:
• Continuity that beeps when a circuit
• Diodes (measuring forward drop and/or polarity) and
Various sensors can be attached to multimeters to take measurements such as:
• Light level
• Acidity/Alkalinity(pH)
• Wind speed
• Relative humidity
Application of breadboard:
A breadboard is used to make up
temporary circuits for testing or
to try out an idea. No soldering is
required so it is easy to change
connections and replace
components. Parts will not be
damaged so they will be available
to re-use afterwards.
References.
[1]. (Online) http://www.vias.org/physics/bk4_04_04b.html
[2]. (Online) http://www.electronics-project
[3]. Introductory Circuit Analysis, 10th Edition
[4]. (Online) http://en.wikipedia.org/wiki/Transformer
[5]. (Online) http://www.allaboutcircuits.com/vol_2/chpt_9/7.html
[6]. (Online) http://en.wikipedia.org/wiki/Breadboard
Short Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and Fabrication
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ionally, multimeters may also measure:
Fahrenheit.
Digital multimeters may also include circuits for:
when a circuit conducts.
(measuring forward drop and/or polarity) and transistors (measuring current gain and other parameters)
rious sensors can be attached to multimeters to take measurements such as:
Breadboard Rofiqul Islam, EEE-061031, RUET
http://www.vias.org/physics/bk4_04_04b.html
project-design.com/LightDependentResistor.html
Introductory Circuit Analysis, 10th Edition by Robert L. Boylestad Prentice Hall 2002
http://en.wikipedia.org/wiki/Transformer
http://www.allaboutcircuits.com/vol_2/chpt_9/7.html
http://en.wikipedia.org/wiki/Breadboard
11
(measuring current gain and other parameters)
Short Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and Fabrication
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[7]. (Online) http://www.kpsec.freeuk.com/breadb.htm
[8]. (Online) http://en.wikipedia.org/wiki/Multimeter
[9]. The art of Electronics by Paul Horowitz
[10]. Basic Engineering Circuit Analysis
[11]. Teach Yourself Electricity & Electronics
[12]. Modern Dictionary of Electronics by Graf
[13]. Illustrated Dictionary of Electronics by Stan Gibilisco
Design Challenge: Design a Negative Power
Variable DC
Power Supply
Short Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and FabricationShort Course on Electronic Project Design and Fabrication
Jointly Organized by: Dept. of EEE and IEEE RUET Student Branch
http://www.kpsec.freeuk.com/breadb.htm
]. (Online) http://en.wikipedia.org/wiki/Multimeter
Teach Yourself Electricity & Electronics by Stan gibilisco
dern Dictionary of Electronics by Graf
[13]. Illustrated Dictionary of Electronics by Stan Gibilisco
r Supply From a Single Positive Supply.
Home Work
12