basic (matter)

8/3/2019 Basic (Matter)

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2011

QUANTA

TECHNICAL SOCIETY

JSSATEN

BASIC ELECTRONICS MODULE


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Resistors

Resistance is the impediment, or in simple words, an obstruction to the flow of electrons through a conductor.

Two parameters associated with resistors: Resistance value in Ohms. Power handling capabilities in watts.

Resistor Identification

colour 1st

Band

2nd

Band

3rd

Band

No of Zeros

4th

Band

Tolerance

Black 0 0 - -

Brown 1 1 0 1%

Red 2 2 00 2%

Orange 3 3 000 -

Yellow 4 4 0,000 -

Green 5 5 00,000 0.5%

Blue 6 6 000,000 0.25%

Violet 7 7 0.10%

Gray 8 8 0.05%

White 9 9 -

Gold X 0.1 5%

Silver X 0.01 10%

No Colour 20%


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There are many different types of resistors used in electronics. Each type is made from different materials. Resistors are

also made to handle different amounts of electrical power.

Some resistors may change their value when voltages are placed across them. These are called voltage dependentresistors ornonlinear resistors.

Most resistors are designed to change their value when the temperature of the resistor changes. Some resistors are also made with a control attached that allows the user to mechanically change the resistance.

These are called variable resistors or potentiometers.

THE WIREWOUND RESISTOR

The first commercial resistors made were formed by wrapping a resistive wire around a ceramic rod (see Figure 3),with

desired heat properties.

Major characteristics:

The value of wirewound resistors remain fairly flat with increasing temperature, but change greatly withfrequency.

It is difficult to precisely control the value of the resistor during construction so they must be measured and sortedafter they are built.


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Capacitors

A capacitor stores electrical energy when charged by a DC source. It can pass alternating current (AC), but blocks direct

current

(DC) except for a very short charging current, called transient current. A device that stores energy in electric field. Two conductive plates separated by a non conductive material. Electrons accumulate on one plate forcing electrons away from the other plate leaving a net positive charge. Think of a capacitor as very small, temporary storage battery.

Capacitor Behavior in DC

When connected to a DC source, the capacitor charges and holds the charge as long as the DC voltage is applied. The capacitor essentially blocks DC current from passing through. A capacitor possess infinite resistance to a DC signal while very small for high frequency signals..Capacitor Behavior in AC

When AC voltage is applied, during one half of the cycle the capacitor accepts a charge in one direction. During the next half of the cycle, the capacitor is discharged then recharged in the reverse direction. During the next half cycle the pattern reverses. It acts as if AC current passes through a capacitor

Types of Capacitors

Following are some of the important types of capacitors used commonly in practical circuits.

1. Ceramic CapacitorThis is one of the most commonly and widely used capacitor in electronic components. A ceramic capacitor is a

capacitor constructed of alternating layers of metal and ceramic, with the ceramic material acting as the dielectric.

They are well suited for use in high frequency applications ranging up to couple of thousands of MHz. These


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capacitors are available from fraction of a pF to 1uF (1000000 pF)

Ceramic cap with value 15x10^4 pF

2. Electrolytic CapacitorAluminum electrodes are used and they are separated by using a thin oxidation membrane. This is a most

common type, polarized capacitor. Cheap, readily available, good for storage of charge. Not very accurate,

leakage, drifting, not suitable for use in HF (High Frequency) circuits, available in very small to very large values

in uF. The most important characteristic of electrolytic capacitors is that they have polarity. They have a positive

and a negative electrode. This means that it is very important that the terminals are connected to the right poles.

3. Tantalum CapacitorsThese capacitors are made of Tantalum Pentoxide. Superior to electrolytic capacitors, excellent temperature and

frequency characteristics. Like electrolytic, tantalum capacitors are polarized so watch the '+' and '-' indicators.

Tantalum capacitors are a little bit more expensive than aluminum electrolytic capacitors. These capacitors are

very stable with temperature and frequency changes. Therefore, tantalum capacitors are used for circuits which

demand high stability in the capacitance values, e.g. analog signal systems, and because the current-spike noise

that occurs with aluminum electrolytic capacitors does not occur here.

4. Metalized Polyester FilmNo polarity, dielectric made of Polyester.Good quality, low drift, temperature stable. Because the electrodes are

thin they can be made really small. Typically used in audio and communication equipments.

5. Trimmer Capacitors


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These use mostly plastic as a dielectric. The capacitance of this type of capacitors can be adjusted using a screw

driver. These capacitors are adjusted at the time of manufacture of the electronic equipment.

6. Variable CapacitorsVariable capacitors are typically air-cored or sometimes uses plastic as a dielectric. Typically connected to knobs

to let the user tune the capacitance, so most of them are designed to connect to a rotating knob. These capacitors

are typically used in radios.

7. Polyester Film CapacitorsThis capacitor uses a thin polyester film as a dielectric. Not as high a tolerance as polypropylene, but cheap and

handy, temperature stable, widely used.

8. Polypropylene CapacitorsMainly used when a higher tolerance is needed than polyester caps can offer. In these capacitors polypropylenefilm is the dielectric.

9. Polystyrene Capacitors


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In this Polystyrene is used as a dielectric. Constructed like a coil inside so not suitable for high frequency

applications. Well used in filter circuits or timing applications using a couple hundred KHz or less.

10.Multilayer Ceramic CapacitorsDielectric is made up of many layers. Small in size, very good temperature stability, excellent frequency stable

characteristics. Used in applications to filter or bypass the high frequency to ground.

11.Silver-Mica CapacitorsMica is used as a dielectric. Used in resonance circuits, frequency filters, and military RF applications. Highly

stable, good temperature coefficient, excellent for endurance because of their frequency characteristics, no large

values, high voltage types available, are relatively expensive.

12.SupercapacitorAn Electric double-layer capacitor, also known as supercapacitor, supercondenser, pseudocapacitor,

electrochemical double layer capacitor (EDLC), or ultracapacitor, is an electrochemical capacitor that has an

unusually high energy density when compared to common capacitors, typically on the order of thousands of times

greater than a high capacity electrolytic capacitor. Whereas a regular capacitor consists of conductive foils and a

dry separator, the supercapacitor crosses into battery technology by using special electrodes and some electrolyte.

There are three types of electrode materials suitable for the supercapacitor. They are: high surface area activated

carbons, metal oxide and conducting polymers. The high surface electrode material, also called Double Layer

Capacitor (DLC), is least costly to manufacture and is the most common. It stores the energy in the double layer

formed near the carbon electrode surface. To know more about supercapacitor and ultracapacitor visit below

links.

Inductors

It is the characteristic of an electrical conductor when coiled that opposes a change in current flow.


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Device that stores energy in a magnetic field. An electromotive force (emf) is induced back into the conductor.

Application: Filtering, phase-shifting Adv over capacitorprovide reactive effect while still completing a DC circuit path.

Inductor Performance With DC Currents

When a DC current is applied to an inductor, the increasing magnetic field opposes the current flow and thecurrent flow is at a minimum.

Finally, the magnetic field is at its maximum and the current flows to maintain the field.As soon as the current source is removed, the magnetic field begins to collapse and creates a rush of current in the other

direction, sometimes at very high voltage.

Inductor Performance With AC Currents

When AC current is applied to an inductor, during the first half of the cycle, the magnetic field builds as if it werea DC current.

During the next half of the cycle, the current is reversed and the magnetic field first has to decrease the reversepolarity in step with the changing current.

These forces can work against each other resulting in a lower current flow.

ACTIVE COMPONENTS:

Active components have the ability to rectify, switch, or amplify signals. Aside from the input signal, most active components require a power supply in order to perform their assigned

functions.

They are often used in dynamic applications such as rectification, switching, amplification, modulation, etc.Examples are:

Bipolar Junction transistors(BJTs) JFETs,MOSFETs OperationalAmplifiers(Op-Amps)

BIPOLAR TRANSISTOR:

The bipolar transistor is a three-terminal device consisting of 3 layers of alternating n- and p-type materialsreferred to as the emitter, base, and collector.

There are two types of bipolar transistor: the NPN and the PNP. In the NPN transistor, the base is composed of ap-type material and is sandwiched by an n-type emitter and an n-type collector. In the PNP, the base is n-type

while the emitter and collector are p-type.

How the transistor operates (and therefore used) depends greatly on how it is electrically stimulated, or biased.


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The transistor may be operated in three different regions: saturation, cut-off, and active. A transistor is said to besaturated if both its base-collector and base-emitter junctions are forward biased. Under this mode, the transistor

is already completely 'on', i.e., the collector current is already very high and no longer increases appreciably even

if more current is fed into the base.

A transistor is in the cut-off region if both of its junctions are reverse biased. Under this mode, the transistor is'off'', i.e., the collector current is very low. A transistor being used as a switch is operated alternately between

saturation and cut-off regions.

A transistor in the active region exhibits a change in collector current that is proportional to the change in basecurrent. A transistor being used as an amplifier is therefore operated in this region. The base-emitter junction of

a transistor in active region is forward-biased while its base-collector junction is reverse-biased .

The arrows in the symbols do imply current directions through Emitter

junction. SL 100 transistor Terminals

SL 100 Transistor Transistor with package T0-220

Junction Field Effect Transistor(JFET):

The Junction Field Effect Transistor (JFET) is a type of field effect transistor whose basic structure consists of asemiconductor bar with ohmic contacts at the end and heavily doped regions on its opposite sides. If the

semiconductor bar is made of n-type material, then it is an n-channel JFET. The JFET is p-channel if the bar is

made of p-type material. The terminals at the ends of the bar correspond to the source and drain of the JFET.

The heavily doped regions on the sides of the bar are connected to serve as the gate of the JFET. The gate regions

are doped to be of opposite type with respect to the channel, so that a p-n junction is formed between the channel

and the gate regions.

N TYPE JFET P TYPE JFET

By applying a voltage across the source and the drain of a JFET, current consisting of majority carriers (electronsfor an n-channel and holes for a p-channel) is caused to flow through the channel. The current flowing through

the channel is controlled by applying a gate voltage Vgs that reverse biases the p-n junction formed by the gate

with respect to the source. The higher the Vgs is, the more the p-n junction is reverse-biased, and the wider the

depletion region across the channel becomes. The wider depletion region results in a narrower channel,

consequently constricting the flow of current through the channel. Varying Vgs therefore varies the current

through the channel for any given voltage across the source and the drain.


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The JFET structure described above is no longer practical to use because of the difficulty with having to diffuse

dopants from two opposite sides of a bar. Most JFETs built onto IC's nowadays involve single-ended geometries that

require doping for the gate from only one side of the channel, i.e., the surface of the wafer. This is achieved by

building the JFET on an epitaxially grown channel over a doped substrate that acts as the second gate.

MOSFET:

The Metal-Oxide Semiconductor Field Effect Transistor (MOSFET) or MOS transistor is a type of transistor thatconsists of a metal layer, an oxide layer, and a semiconductor layer. The semiconductor layer is usually in the

form of single-crystal silicon substrate doped precisely to perform transistor action. The oxide is usually in the

form of a silicon dioxide layer that insulates the semiconductor layer from the metal layer. The metal layer is

used as contact for providing voltage inputs to the MOS transistor.

N Type Enhancement Mosfet

The MOS transistor consists of three terminals: a gate, a source, and a drain. These are equivalent to the base,emitter, and collector of a bipolar transistor. The metal layer of the MOS transistor serves as the gate, while thesource and drain are fabricated on the silicon substrate.

Like a bipolar transistor, the current flowing through a MOS transistor is controlled by the input at its gate.However, unlike a bipolar transistor which is controlled by the amount of current into its base, a MOS transistor

is controlled by the voltage level at its gate.

The source and drain of a MOS transistor are created on the silicon substrate in such a way that they are'sandwiching' the gate. The source and drain are doped to be of the same material type, which should be different

from the doping received by the substrate. A MOS transistor is referred to as a P-channel MOSFET, or PMOS, if

the source and drain are p-type, and the substrate is n-type. It is an N-channel MOSFET, or NMOS, if the source

and drain are n-type, and the substrate is p-type.

The area under the gate is known as the channel. The conductivity of the channel may be controlled through thevoltage level applied to the gate. For instance, in an NMOS, the major carrier is the electron, so the channel

becomes more conductive by applying a positive voltage at the gate, which tends to attract more electrons from

the substrate into the channel. The layer formed by these attracted electrons is known as the 'inversion layer',

since electrons are the minority carriers of the p-substrate.

If the source of the NMOS is more negative than the drain while a sufficiently positive voltage is applied to thegate, current would pass through the transistor. Removing the positive voltage at the gate would significantly

decrease the conductivity of the channel, constricting the flow of electrons. A MOS transistor operating in this

manner is known as an enhancement-mode MOS transistor, because it is normally open and conducts only when

the channel is 'enhanced.' On the other hand, a normally conducting transistor is known as a depletion-mode

transistor, since its conduction is controlled by 'depleting' the normally-present channel.

Operational Amplifiers(OP-AMPs):

An Operational Amplifier, or Op Amp, is a dual-input, single-output linear amplifier that exhibits a high open-loop gain, high input resistances, and a low output resistance.

One of the inputs of an operational amplifier amp is non-inverting while the other is inverting.

The output Vout of an operational amplifier without feedback (also known as open-loop) is given by the formula:Vout = A (Vp-Vn) where A is the open-loop gain of the op amp, Vp is the voltage at the non-inverting input, and

Vn is the voltage at the inverting input.


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Depending on its feedback circuit and biasing, an op amp can be made to add, subtract, multiply, divide, negate, and,interestingly, even perform calculus operations such as differentiation and integration. This is the reason why we call

them as Operational Amplifiers.

LM 741

PIN CONFIGURATION OF 741

Because of the very high resistance exhibited by the inputs of an op amp, the currents flowing through them are very

small. The current flowing in or out of an op amp's input pin, known as input bias current, is basically just leakage

current at the base or gate of the input transistor of that input, which is why it is very small. When solving

voltage/current equations for op amp circuits, the input currents are usually assumed to be zero. For most of the

commonly-used op-amp circuits, this means that the total output current of the op amp is flowing through thefeedback circuit between the output and the inverting input (the feedback is usually connected to the inverting input

for operation stability).

Semiconductor Basics

Diodes are made from a single piece ofSemiconductor material which has a positive "P-region" at one end and a

negative "N-region" at the other, and which has a resistivity value somewhere between that of a conductor and an

insulator. But what is a "Semiconductor" material?, firstly let's look at what makes something either a Conductor or an

Insulator.

Resistivity Chart

Notice also that there is a very small

margin between the resistivity of the

conductors such as silver and gold,

compared to a much larger margin for

the resistivity of the insulators between

glass and quartz. The resistivity of all

the materials at any one time also

depends upon their temperature.


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Semiconductor Basics

Semiconductors materials such as silicon (Si), germanium (Ge) and gallium arsenide (GaAs), have electrical properties

somewhere in the middle, between those of a "conductor" and an "insulator". They are not good conductors nor good

insulators (hence their name "semi"-conductors).

This process of adding impurity atoms to semiconductor atoms (the order of 1 impurity atom per 10 million (or more)

atoms of the semiconductor) is called Doping.

The diagram above shows the structure and lattice of a 'normal' pure crystal of

Silicon.

N-type Semiconductor Basics

In order for our silicon crystal to conduct electricity, we need to introduce an impurity atom such as Arsenic, antimony.

These pentavalent impurities do provide excess electrons hence enhancing conduction

The diagram above shows the structure and lattice of the donor impurity atom

Antimony.

P-Type Semiconductor Basics

Semiconductors lattice are doped with trivalent impurities such as boron.Therefore,


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a P-type semiconductor has more holes than electrons.

The diagram above shows the structure and lattice of the acceptor impurity atom

Boron.

The Junction Diode

Junction Diode Symbol and Static I-V Characteristics.

But before we can use the PN junction as a practical device or as a rectifying device we need to firstly bias the junction,

ie connect a voltage potential across it. On the voltage axis above, "Reverse Bias" refers to an external voltage potential

which increases the potential barrier. An external voltage which decreases the potential barrier is said to act in the

"Forward Bias" direction.

There are two operating regions and three possible "biasing" conditions for the standard Junction Diode and these are:

1. Zero Bias - No external voltage potential is applied to the PN-junction.


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2. Reverse Bias - The voltage potential is connected negative, (-ve) to the P-type material and

positive, (+ve) to the N-type material across the diode which has the effect ofIncreasing the

PN-junction width.

3. Forward Bias - The voltage potential is connected positive, (+ve) to the P-type material and

negative, (-ve) to the N-type material across the diode which has the effect ofDecreasing the

PN-junction width.

The Zener Diode

The Zener Diode or "Breakdown Diode" as they are sometimes called, are basically the same as the standard PN

junction diode but are specially designed to have a low pre-determined Reverse Breakdown Voltage that takes

advantage of this high reverse voltage. The point at which a zener diode breaks down or conducts is called the "Zener

Voltage" (Vz).

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 for low-current applications.

Light Emitting Diodes

They are the most visible type of diode, that emit a fairly narrow bandwidth of either visible light at different coloured

wavelengths, invisible infra-red light for remote controls or laser type light when a forward current is passed through

them.

INSIDE THE LED:

A "Light Emitting Diode" or LED as it is more commonly called, is basically just a specialised type of PN junction

diode, made from a very thin layer of fairly heavily doped semiconductor material. When the diode is forward biased,

electrons from the semiconductors conduction band recombine with holes from the valence band releasing sufficient

energy to produce photons which emit a monochromatic (single colour) of light. Because of this thin layer a reasonable


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number of these photons can leave the junction and radiate away producing a coloured light output. Then we can say that

when operated in a forward biased direction Light Emitting Diodes are semiconductor devices that convert electrical

energy into light energy.

Light Emitting Diode Colours

Light Emitting Diodes are made from exotic semiconductor compounds such as Gallium Arsenide (GaAs), Gallium

Phosphide (GaP), Gallium Arsenide Phosphide (GaAsP), Silicon Carbide (SiC) or Gallium Indium Nitride (GaInN) all

mixed together at different ratios to produce a distinct wavelength of colour.

Light emitting diodes are available in a wide range of

colours with the most common being RED, AMBER,

YELLOW and GREEN and are thus widely used as visual

indicators and as moving light displays.

Recently developed blue and white coloured LEDs are also

available but these tend to be much more expensive than the

normal standard colours due to the production costs .

WHAT IS RECTIFIER?

Any circuit that converts bidirectional current flow across a load to a unidirectional current across a load i.e the

function of rectifier is to convert ac voltage into dc voltage.

NEED FOR RECTIFIER CIRCUIT.

Most of the devices in electronics equipments require dc voltage but supply available to us in our home or industry is an

ac supply so we need a rectifier circuit that can convert the bidirectional current to unidirectional current and on passing

the rectifiers output through a filter we get filtered dc output.

BLOCK DIAGRAM OF POWER SUPPLY

Typical LED Characteristics

Semiconductor

MaterialWavelength Colour VF @ 20mA

GaAs 850-940nm Infra-Red 1.2v

GaAsP 630-660nm Red 1.8v

GaAsP 605-620nm Amber 2.0v

GaAsP:N 585-595nm Yellow 2.2v

AlGaP 550-570nm Green 3.5v

SiC 430-505nm Blue 3.6v

GaInN 450nm White 4.0v


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PIV(PEAK INVERSE VOLTAGE)

PIV is an important factor in the designing of a rectifier.PIV is the max negative voltage or reverse voltage the diode can

withstand without entering zener or avalanche breakdown.PIV is always of concern when operated in reverse biased

case.PIV should always be lesser than the reverse breakdown voltage across the diode.

NOTE:IT IS ALWAYS ADVISABLE TO PREFER A CIRCUIT IN WHICH PIV ACROSS THE DIODE IS

LESS.

(PIV


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BRIDGE RECTIFIER

WORKING:

The output waveform is similar to FULL WAVE BRIDGE RECTIFIER.It consists of four diodes .Two diodes of the four

diodes conduct during each half the +ve andve half of the cycle.Thus we get a positive half cycle across the load

corresponding to each half the input ac supply.

NOTE:PIV FOR BRIDGE RECTIFIER IS V ,WHICH BECOMES ITS ADVANTAGE OVER THE CENTERTAPPED

FULL WAVE RECTIFIER.

ADVANTAGES OF BRIDGE RECTIFIER OVER CENTER TAPPED FULL WAVE RECTIFIER.

*THE TRANSFOMER UTILISATION FACTOR FOR BRIDGE RECTIFIER IS MORE THAN CENTERTAPPED.

*THE PIV FOR BRIDGE RECTIFIER IS LESS THAN THAT OF PIV FOR CENTERTAPPED RECTIFIER.

EXAMPLE: SUPPOSE YOU HAVE A DIODE WHOSE BREAKDOWN VOLTAGE IS 10 VOLT AND THE

MAX.INPUT SIGNAL V IS 6 VOLT .SO IF WE USE CENTERTAPPED RECTIFIER ,ITS PIV IS 2*V=12 V HENCE

THE DIODE ENTERS THE ZENER OR AVALANCHE REGION.BUT IF USE BIDGE RECTIFIER ,ITS PIV IS V=6

V,HENCE IT DOES NOT ENTERS THE ZENER OR AVALANCHE RGION.

NOTE:WE USE BRIDGE RECTIFIER IN HIGH VOLTAGE APPLICATION.

MEMRISTOR:

Memristors are basically a fourth class of electrical circuit, joining the resistor, the capacitor, and the inductor,that exhibit their unique properties primarily at the nanoscale. .

HISTORY- The memristor's story starts nearly four decades ago with a flash of insight by IEEE Fellow andnonlinear circuit theory pioneer Leon Chua. Examining the relationships between charge and flux in resistors,


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capacitors, and inductors in a 1971 paper, Chua postulated the existence of a fourth element called the memory

resistor.

Such a device, he figured, would provide a similar relationship between magnetic flux and charge that a resistor

gives between voltage and current. However, it has a nonlinear relationship between current and voltage, like

thevaristor.

A varistor is an electronic component with a "diode-like"nonlinearcurrentvoltage characteristic. Varistors areoften used to protectcircuitsagainst excessive

transientvoltagesby incorporating them into the circuit in such a way that, when triggered, they will shunt the

current created by the high voltage away from the sensitive components

A VARISTOR

The below diagram depicts the the function of the memristor i.e. When current flows in one directionthrough the device, theelectrical resistanceincreases; and when current flows in the opposite direction, the

resistance decreases. When the current is stopped, the component retains the last resistance that it had, and

when the flow of charge starts again, the resistance of the circuit will be what it was when it was last active.

. HP is currently working with Hynix Semiconductor to develop the next generation of computermemory. ... or ReRAM for short, will be built upon memristor technology.
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WORKING OF A MEMRISTOR- When current flows in one direction through the device, theelectricalresistanceincreases; and when current flows in the opposite direction, the resistance decreases When the current is

stopped, the component retains the last resistance that it had, and when the flow of charge starts again, the

resistance of the circuit will be what it was when it was last active.

The resistance of a memristor depends on the integral of the input applied to the terminals (rather than on theinstantaneous value of the input as in a varistor).Since the element "remembers" the amount of current that has

passed through it in the past, it was tagged by Chua with the name "memristor."

MATERIAL OF MEMRISTOR- The two terminal memristor above uses titanium dioxide (TiO2) as theresistive material (other materials can be used such as SiO2, but apparently TiO2 works better).

HOW CAN TiO2 ACT AS A MEMRISTOR???Williams found an ideal memristor in titanium dioxide--the stuff of white paint and sunscreen. Like silicon,

titanium dioxide (TiO 2 ) is a semiconductor, and in its pure state it is highly resistive. However, it can be doped

with other elements to make it very conductive. In TiO 2 , the dopants don't stay stationary in a high electric field;

they tend to drift in the direction of the current.Such mobility is poison to a transistor, but it turns out that's

exactly what makes a memristor work. Putting a bias voltage across a thin film of TiO 2 semiconductor that has

dopants only on one side causes them to move into the pure TiO 2 on the other side and thus lowers the resistance.

Running current in the other direction will then push the dopants back into place, increasing the TiO 2 'sresistance.

HP Labs is now working out how to manufacture memristors from TiO 2 and other materials and figuring out the

physics behind them.

HOW IS IT DIFFERENT FROM A RESISTOR,CAPACITOR OR AN INDUCTOR???

The reason that the memristor is radically different from the other fundamental circuit elements is that, unlike

them, it carries a memory of its past. When you turn off the voltage to the circuit, the memristor still remembers

how much was applied before and for how long. That's an effect that can't be duplicated by any circuit

combination of resistors, capacitors, and inductors, which is why the memristor qualifies as a fundamental circuit

element.

A linear time-invariant memristor, with a constant value forM, is simply a conventional resistor.The memristor isessentially a two-terminal variable resistor, with resistance dependent upon the amount of charge q that has

passed between the terminals.
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the memristor is formally defined[4]as a two-terminal element in which the flux linkage (or integral of voltage)m between the terminals is a function of the amount ofelectric chargeQ that has passed through the device. Each

memristor is characterized by its memristance M function describing the charge-dependent rate of change of flux

with charge.

To relate the memristor to the resistor, capacitor, and inductor, it is helpful to isolate the termM(q), whichcharacterizes the device, and write it as a differential equation:

M = dm / dQ,

where Q is defined by I = dQ/dt, and mis defined by V = dm/dt

CATHODE RAY OSCILLOSCOPE(CRO):INTRODUCTION:

The cathode-ray oscilloscope (CRO) is a common laboratory instrument that provides accurate time and amplitude

measurements of voltage signals over a wide range of frequencies. Its reliability, stability, and ease of operation makes it

suitable as a general purpose laboratory instrument.

CONSTRUCTION:

The cathode ray is a beam of electrons which are emitted by the heated cathode (negative electrode) and acceleratedtoward the fluorescent screen.

The assembly of the cathode, intensity grid, focus grid, and accelerating anode (positive electrode) is called an electrongun. Its purpose is to generate the electron beam and control its intensity and focus.

Between the electron gun and the fluorescent screen, are two pair of metal plates - one oriented to provide horizontaldeflection of the beam and one pair oriented to give vertical deflection to the beam. These plates are thus referred to as
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the horizontal and vertical deflection plates. The combination of these two deflections allows the beam to reach any

portion of the fluorescent screen.

Wherever the electron beam hits the screen, the phosphor is excited and light is emitted from that point. This conversionof electron energy into light allows us to write with points or lines of light on an otherwise darkened screen.

Thus the required waveform is displayed on the screen based upon the horizontal and vertical deflections provided by thetwo sets of deflection plates.

Measuring voltage and time period:

The trace on an oscilloscope screen is a graph of voltage against time. The shape of this graph is determined by the nature

of the input signal.

In addition to the properties labelled on the graph, there is frequency which is the number of cycles per second.

These properties apply to any signal with a constant shape

VOLTAGE:

Voltage is shown on the vertical y-axis and the scale is determined by the Y AMPLIFIER (VOLTS/CM) control. Usually

peak-peak voltage is measured because it can be read correctly even if the position of 0V is not known. The amplitude is

half the peak-peak voltage.

TIME-PERIOD:

Time is shown on the horizontal x-axis and the scale is determined by the TIMEBASE (TIME/CM) control. The time

period (often just called period) is the time for one cycle of the signal. The frequency is the number of cyles per second,

frequency = 1/time period

Lissajous Figures:

When sine-wave signals of different frequencies are input to the horizontal and vertical amplifiers a stationary pattern is

formed on the CRT , when the ratio of the two frequencies is an intergral fraction such as 1/2, 2/3, 4/3, 1/5, etc. Thesestationary patterns are known asLissajous figures and can be used for comparison measurement of frequencies.It may be

difficult to maintain the Lissajous figures in a fixed configuration because the two oscillators are not phase and frequency

locked. Their frequencies and phase drift slowly causing the two different signals to change slightly with respect to each

other.

Lissajous figures with horizontal to vertical frequency ratios of:

a)1:1 b)2:1 c)1:2 d)3:1

Lissajous figures may also be used for phase-shift measurements.

A Lissajous figure is produced by taking two sine waves at the two channels of CRO and the oscilloscope is used in XY


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mode

When the two sine waves are of equal frequency and in-phase, you get a diagonal line to the right

When the two sine waves are of equal frequency and 180 degrees out-of-phase you get a diagonal line to the left.

When the two sine waves are of equal frequency and 90 degrees out-of-phase you get a circle.

Dual-Beam Oscilloscope:

The dual-beam analog oscilloscope can display two signals simultaneously. A special dual-beam CRT generates and

deflects two separate beams. Although multi-trace analog oscilloscopes can simulate a dual-beam display with chop andalternate sweeps, those features do not provide simultaneous displays. (Real time digital oscilloscopes offer the same

benefits of a dual-beam oscilloscope, but they do not require a dual-beam display.)

Use of oscillator in emerging technology:

Waveform analysis in communication system design. Output analysis designed electronic circuits and their response to wards different voltage and current inputs. In determination of time constant, phase shift, frequency, pulses width, and amplitude variations of the signal under test. Study of noise spectrum in received signals at the receiver section of communication systems. For study of wave propagation of in laboratories. For visualization of physical quantities after their conversion into proper electrical form so that the changes occurring

over there may be observe and study may become even simpler.

Disadvantages of cathode ray oscilloscope:

It is a very sensitive device and is often noise prone i.e. upon application small signals to them noise may enter in thesystem through open wiring, exposed metallic components and unprotected parts. So they require complete isolation from

noise prone sources.

When it comes to analyse very high frequency signals a general cathode ray oscilloscope becomes incapable to producesome reliable result because that much of variations are not supported by normal electronic components used in them.


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Very sudden changes cannot be observed with normal CRO, particularly when they are occurring at very high frequencybecause they occur for a very small instant of time and human eye remains incapable of observing them.

Cathode ray oscilloscope cannot be used for study of high voltage signals and in order to study them they first need to beconverted to low voltage, this puts a limiting mark upon application of these instruments.

They are a lot of control terminals over the control panel that leads to a greater complexity of the device making itdifficult to use.

Digital storage oscilloscopes:Now-a-days,Digital Storage Oscilloscopes are preferred over analog oscilloscopes,because in DSOs waveforms can be

stored in digital form,without any kind of distortion.

The digital storage oscilloscope is now the preferred type for most industrial applications, although simple analog CROs

are still used in many applications. It replaces the unreliable storage method used in analog storage scopes with

digital memory, which can store data as long as required without degradation

MULTIMETERS:

A multimeter also known as a VOM (Volt-Ohm meter), is an electronic measuring instrument that combinesseveral measurement functions in one unit. A typical multimeter may include features such as the ability to

measure voltage, current and resistance.

Multimeters may use analog or digital circuitsanalog multimeters (AMM) and digital multimeters (oftenabbreviated DMM or DVOM.) .Analog instruments are usually based on a microammeter whose pointer moves

over a scale calibrated for all the different measurements that can be made; digital instruments usually display

digits, but may display a bar of a length proportional to the quantity being measured

Multimeters are very useful test instruments. By operating a multi-position switch on the meter they can bequickly and easily set to be a voltmeter, an ammeter or an ohmmeter. They have several settings (called 'ranges')

for each type of meter and the choice of AC or DC. Some multimeters have additional features such as transistor

testing and ranges for measuring capacitance and frequency.

They can be used to troubleshoot electrical problems in a wide array of industrial and household devices such aselectronic equipment, motor controls, domestic appliances, power supplies, and wiring systems.


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PMMC(Permanent Magnet Moving Coil) instruments:

Multimeters are primarily based upon PMMC(Permanent Magnet Moving Coil) instruments.The action of theseinstruments is based on the motoring principle.

When a current carrying coil is placed in the magnetic field produced by permanent magnet, the coil experiencesa force and moves. As the coil is moving and the magnet is permanent, the instrument is called permanent magnet

moving coil instrument. This basic principle is called DArsonval principle. The amount of force experienced by

the coil is proportional to the current passing through the coil.

The moving coil is either rectangular or circular in shape. It has number of turns of fine wire.The coil issuspended so that it is free to turn about its vertical axis. The coil is placed in uniform, horizontal and radial

magnetic field of a permanent magnet in the shape of a horse-shoe. The iron core is spherical if coil is circular

and is cylindrical if the coil is rectangular. Due to iron core, the deflecting torque increase, increasing the

sensitivity of the instrument.

The controlling torque is provided by two phosphor bronze hair springs. The damping torque is provided by eddy current damping. It is obtained by movement of aluminium former,

moving in the magnetic field of the permanent magnet.

The pointer moves over a graduated scale. The pointer has light weight so that it deflects rapidly. The weight ofthe instrument is normally counter balanced by the weights situated diametrically opposite and rapidly connected

to it.The pointer deflections are directly proportional to the current passing through the coil.


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Quantities measured:

Voltage, alternating and direct, in volts. Current, alternating and direct, in amperes. The frequency range for which AC measurements are accurate must be specified. Resistance in ohms.

Additionally, some multimeters 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, with an appropriate temperature test probe, often a thermocouple.

Resolution versus Accuracy:

Resolution and accuracy in a multimeter are not equal. The resolution of a multimeter is the smallest part of the scale

which can be shown. The resolution is scale dependent and in high end digital multimeters it can be configured, with

higher resolution measurements taking longer to complete. For example, a multimeter that has a 1mV resolution on a

10V scale can show changes in measurements in 1mV increments. Absolute accuracy is the error of the measurement

compared to a perfect measurement. Relative accuracy is the error of the measurement compared to the device used to

calibrate the multimeter. Most multimeter datasheets provide relative accuracy. To compute the absolute accuracy

from the relative accuracy of a multimeter add the absolute accuracy of the device used to calibrate the multimeter to

the relative accuracy of the multimeter

DIGITAL MULTIMETERS:

All digital meters contain a battery to power the display so they use virtually no power from the circuit under test.

This means that on their DC voltage ranges they have a very high resistance (usually called input impedance) of 1M

or more, usually 10M, and they are very unlikely to affect the circuit under test.

Typical ranges for digital multimeters like the one illustrated:

(the values given are the maximum reading on each range)

DC Voltage: 200mV, 2000mV, 20V, 200V, 600V. AC Voltage: 200V, 600V. DC Current: 200A, 2000A, 20mA, 200mA, 10A*. ( *The 10A range is usually unfused and connected via

a special socket.)

AC Current: None. Resistance: 200, 2000, 20k, 200k, 2000k, Diode Test.

Digital meters have a special diode test setting because their resistance ranges

cannot be used to test diodes and other semiconductors.


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Measuring voltage and current with a multimeter:

Select a range with a maximum greater than you expect the reading to be. Connect the meter, making sure the leads are the correct way round. (Digital meters can be safely connected

in reverse, but an analogue meter may be damaged.)

If the reading goes off the scale: immediately disconnect and select a higher range.Measuring voltage at a point:

Connect the black (negative -) lead to 0V, normally the negative terminal of the battery or power supply.

Connect the red (positive +) lead to the point you where you need to measure the voltage. The black lead can be left permanently connected to 0V while you use the red lead as a probe to measure

voltages at various points.

You may wish to fit a crocodile clip to the black lead of your multimeter to hold it in place while doingtesting like this.

Measuring resistance with a multimeter:

Measuring resistance with a DIGITAL multimeter:

Set the meter to a resistance range greater than you expect the resistance to be.

Touch the meter probes together and check that the meter reads zero. Put the probes across the component.

(Avoid touching more than one contact at a time or your resistance will upset the reading)

Measuring resistance with an ANALOGUE multimeter:

The resistance scale on an analogue meter is normally at the top, it is an unusual scale because it reads backwards and

is not linear (evenly spaced). This is unfortunate, but it is due to the way the meter works.

Set the meter to a suitable resistance range. Hold the meter probes together and adjust the control on the front of the meter which is usually labelled "0

ADJ" until the pointer reads zero (on the RIGHT remember!).

Put the probes across the component.


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Testing a diode with a multimeter:

The techniques used for each type of meter are very different so they are treated separately:

Diodes

a = anode

k = cathode

Testing a diode with a DIGITAL multimeter:

Digital multimeters have a special setting for testing a diode, usually labelled with the diode symbol.

Connect the red (+) lead to the anode and the black (-) to the cathode. The diode should conduct and themeter will display a value (usually the voltage across the diode in mV, 1000mV = 1V).

Reverse the connections. The diode should NOT conduct this way so the meter will display "off the scale"(usually blank except for a 1 on the left).

Testing a diode with an ANALOGUE multimeter:

Set the analogue multimeter to a low value resistance range such as 10. It is essential to note that the polarity of analogue multimeter leads is reversed on the resistance ranges, so the

black lead is positive (+) and the red lead is negative (-)! This is unfortunate, but it is due to the way the meter

works. Connect the black (+) lead to anode and the red (-) to the cathode. The diode should conduct and the meter

will display a low resistance (the exact value is not relevant).

Reverse the connections. The diode should NOT conduct this way so the meter will show infinite resistance(on the left of the scale)

Testing a transistor with a multimeter:

Set a digital multimeter to diode test and an analogue multimeter to a low resistance range such as 10, as described

above for testing a diode.

Test each pair of leads both ways (six tests in total):

The base-emitter (BE) junction should behave like a diode and conduct one way only. The base-collector (BC) junction should behave like a diode and conduct one way only. The collector-emitter (CE) should not conduct either way.

INTEGRATED CIRCUITS:

An integrated circuit (IC), sometimes called a chip ormicrochip, is asemiconductorwafer on which thousands or

millions of tiny resistors, capacitors, andtransistors are fabricated. An IC can function as anamplifier,oscillator,
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timer, counter, computer memory, or microprocessor.

A particular IC is categorized as either linear (analog) ordigital, depending on its intended application.

Linear ICs have continuously variable output (theoretically capable of attaining an infinite number of states) that dependson the input signal level. As the term implies, the output signal level is a linear function of the input signal level. Ideally,

when the instantaneous output is graphed against the instantaneous input, the plot appears as a straight line. Linear ICs are

used as audio-frequency (AF) and radio-frequency (RF) amplifiers. Theoperational amplifier(op amp) is a commondevice in these applications.

Digital ICs operate at only a few defined levels or states, rather than over a continuous range of signal amplitudes. Thesedevices are used in computers, computer networks, modems, and frequency counters. ICs 7400,7402,7432,7408 are some

of the commonly used Digital ICs.

Classification of Integrated Circuits based on Technology:

Small Scale Integration or (SSI) - Contain up to 10 transistors or a few gates within a single package such asAND, OR, NOT gates.

Medium Scale Integration or (MSI) - between 10 and 100 transistors or tens of gates within a single package and

perform digital operations such as adders, decoders, counters, flip-flops and multiplexers.

Large Scale Integration or (LSI) - between 100 and 1,000 transistors or hundreds of gates and perform specific

digital operations such as I/O chips, memory, arithmetic and logic units.

Very-Large Scale Integration or (VLSI) - between 1,000 and 10,000 transistors or thousands of gates and perform

computational operations such as processors, large memory arrays and programmable logic devices.

Super-Large Scale Integration or (SLSI) - between 10,000 and 100,000 transistors within a single package and

perform computational operations such as microprocessor chips, micro-controllers, basic PICs and calculators.

Ultra-Large Scale Integration or (ULSI) - more than 1 million transistors - the big boys that are used in computers

CPUs, GPUs, video processors, micro-controllers, FPGAs and complex PICs.

LOGIC FAMILIES:

Transistortransistor logic (TTL) is a class ofdigital circuitsbuilt frombipolar junction transistors(BJT)andresistors. It is called transistortransistor logic because both the logic gating function (e.g.,AND) and the

amplifying function are performed by transistors (contrast withRTLandDTL).

Fundamental TTL gate
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Two-input TTLNAND gatewith a simple output stage (simplified). TTL inputs are the emitters of amultiple-emitter transistor. This IC structure is functionally equivalent to

multiple transistors where the bases and collectors are tied together. The output is buffered by acommon

emitteramplifier.

Input logical ones. When all the inputs are held at high voltage, the baseemitter junctions of the multiple-emitter transistor are backward-biased. In contrast with DTL, small (about 10 A) "collector" currents are drawn

by the inputs since the transistor is in areverse-active mode(with swapped collector and emitter). The base

resistor in combination with the supply voltage acts as a substantially constant current source. It passes current

through the basecollector junction of the multiple-emitter transistor and the baseemitter junction of the output

transistor thus turning it on; the output voltage becomes low (logical zero).

Input logical zero. If one input voltage becomes zero, the corresponding baseemitter junction of the multiple-emitter transistor connects in parallel to the two connected in series junctions (the basecollector junction of the

multiple-emitter transistor and the baseemitter junction of the second transistor). The input baseemitter junction

steer all the base current of the output transistor to the input source (the ground). The base of the output transistor

is deprived of current causing it to go into cut-of and the output voltage becomes high (logical one). During the

transition the input transistor is briefly in its active region; so it draws a large current away from the base of the

output transistor and thus quickly discharges its base. This is a critical advantage of TTL over DTL that speeds up

the transition over a diode input structure

DISADVANTAGE- The main disadvantage of TTL with a simple output stage is the relatively high output resistance at output logical

"1" that is completely determined by the output collector resistor. It limits the number of inputs that can be

connected

Examples of this type of gate are the 7401 and 7403 series.NOTE-

Standard TTL circuits operate with a 5-voltpower supply. A TTL input signal is defined as "low" when between0 V and 0.8 V with respect to the ground terminal, and "high" when between 2.2 V and 5 V (precise logic levels

vary slightly between sub-types and by temperature). TTL outputs are typically restricted to narrower limits of

between 0 V and 0.4 V for a "low" and between 2.6 V and 5 V for a "high", providing 0.4V ofnoise immunity.

Comparison with other logic families

TTL devices consume substantially more power than equivalentCMOSdevices at rest, but power consumptiondoes not increase with clock speed as rapidly as for CMOS devices. Compared to contemporaryECLcircuits,

TTL uses less power and has easier design rules but is substantially slower. Designers can combine ECL and TTL

devices in the same system to achieve best overall performance and economy, but level-shifting devices are

required between the two logic families. TTL is less sensitive to damage fromelectrostatic dischargethan early

CMOS devices.

Applications

Before the advent ofVLSIdevices, TTL integrated circuits were a standard method of construction for theprocessors of mini-computer and mainframe processors; such as theDECVAXandData GeneralEclipse, and for

equipment such as machine tool numerical controls, printers and video display terminals.

Asmicroprocessorsbecame more functional, TTL devices became important for "glue logic" applications, such

as fast bus drivers on a motherboard, which tie together the function blocks realized in VLSI elements.

INTRODUCTION PMOS technology originally dominated MOS manufacturing. However because NMOS devices can be made

smaller and thus operate faster ,nd also it requires less power supply yb has than PMOS, NMOS technology has

virtually replaced PMOS.. nevertheless , it is important to be familiar with PMOS transistors for two reasons-
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PMOS devices are still used available for discretecircuit design and more importantly both PMOS nd NMOS

transistors are utilized in complementary MOS or CMOS circuits, which is currently the dominant MOS

technology.

Although cmos circuits are somewhat more difficult to fabricate than NMOS. At the present time CMOS is themost widely used of all IC technologies. CMOS technology has virtually replaced designs based on NMOS

transistors alone.

Figure shows a cross section of a CMOS chip illustrating how the PMOS and NMOS transistors are fabricated .

observe that while NMOS transistor is implemented directly in the p-type substrate , the PMOS transistor is

fabricated in a specially created n region, known as n well. The two devices are isolated from each other by a

thick region of oxide that functions as an insulator.

CONNECTORS

An electrical connector is an electro-mechanical device for joining electrical circuits as an interface using a mechanical

assembly. The connection may be temporary, as for portable equipment, require a tool for assembly and removal, or serve

as a permanent electrical joint between two wires or devices.Register Jack

A registered jack (RJ) is a standardized physicalnetwork interfaceboth jack construction and wiring patternforconnecting telecommunications or data equipment to a service provided by alocal exchange carrierorlong distance

carrier. The standard designs for these connectors and their wiring are named RJ11, RJ14, RJ21, RJ48, etc.

RJ11

More commonly known as a phone jack or phone connector, the RJ-11 is short for Registered

Jack-11 and is a four or six wire connection primarily used for telephones and computer modem connectors. In the

picture to the right, is an example image of what the RJ-11 phone connection looks like.Although this cable can be used to connect your modem to the Internet it should not be confused with the RJ-

45 connector, which is used with your network card

RJ14

RJ14 connectors are used for a 2-line telephone jack or otherdevice, such as a modem or answering machine.

RJ12

An RJ-12 Plug has 2 conductors and is used for 1 line.

RJ12 RJ14
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ST Connectors The ST (Straight Tip) connector is a fiber optic connector which uses a plug and socket which is locked

in place with a half-twist bayonet lock. The ST connector was the first default standard for fiber optic cabling. They are

amongst the most frequently used fiber optic connectors in networking applications. They are cylindrically shaped with

twist lock coupling, 2.5mm keyed ferrule

SC Connectors

The SC connector is a fiber optic connector with a push-pull latching mechanism which provides quick insertion and

removal while also ensuring a positive connection. SC is an abbreviation for Subscriber Connector.

These connectors are commonly used for most modern network applications.

BNC Connectors

The BNC connector(BayonetNeillConcelman) is a common type ofRF connectorused forcoaxial cable. It is used

withradio,television, and otherradio-frequencyelectronicequipment, test instruments, video signals, and was once apopular computer network connector. BNC connectors are made to match thecharacteristic impedanceof cable at either

50 ohms or 75 ohms. It is usually applied for frequencies below 3 GHz and voltages below 500 Volts.

VGA Connector

AVideo Graphics Array (VGA) connector is a three-row 15-pin DE-15connector. The 15-pin VGA connector is found

on many video cards, computer monitors, and some high definition television sets. On laptop computers or other small

devices, a mini-VGA port is sometimes used in place of the full-sized VGA connector.

HDMI
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HDMI (High-Definition Multimedia Interface) is a compact audio/video interface for transmitting uncompressed

digital data. HDMI connects digital audio/video sources (such as set-top boxes, DVD players, HD DVD players, Blue-ray

Disc players, AVCHD camcorders, personal computers (PCs), video game consoles such as the PlayStation 3 and Xbox

360, and AV receivers) to compatible digital audio devices, computer monitors, video projectors, tablet computers,

and digital televisions.

IEEE-1394 OR FIREWIRE

IEEE-1394 is a communication technology that was developed by Apple in the early 1990s, at about the same time

as USB. The original IEEE-1394 standard is known as FireWire, IEEE-1394a.Occasionally it is referenced as

FireWire 400 due to its maximum data transfer speed of 400 Mbps. Because it was more costly to implement than

USB, IEEE-1394 did not become as popular an interface for peripheral devices. However, its fast performance and

stability have made it a popular choice for high-bandwidth applications such as digital video and portable storage.One of IEEE-1394's biggest advantages over USB is that it does not require a host controller. This means that two

IEEE-1394 devices can communicate without the use of a computer. For example, video can be dubbed from one DV

camcorder to another through the use of an IEEE-1394 connection. More recently, the development of FireWire 800

(IEEE-1394b) arose with the maximum data transfer speed of 800 Mbps.

CABLES

A cable is a guided media used as communication channels. A cable is two or more wires running side by side and

bonded, twisted or braided together to form a single assembly

Twisted Pair Cable

Twisted paircablingis a type of wiring in which two conductors (the forward and return conductors of a singlecircuit)

are twisted together for the purposes of canceling outelectromagnetic interference(EMI) from external sources; for

instance,electromagnetic radiationfrom unshielded twisted pair (UTP) cables, andcrosstalkbetween neighboring pairs

There are two types of twisted pair cables available.

1.Unshielded twisted pair (UTP)

UTP cables are found in manyEthernetnetworks and telephone systems. For indoor telephone applications, UTP is often

grouped into sets of 25 pairs according to a standard25-pair color codeUTPcableis also the most common cable used incomputer networking. ModernEthernet, the most common data

networking standard, utilizes UTP cables. Twisted pair cabling is often used in data networks for short and medium

length connections because of its relatively lower costs compared tooptical fiberandcoaxial cable.

UTP cable can have maximum segment length of 100 meters and supports maximum bandwidth of 100 Mbps.
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An optical fiber cable is acablecontaining one or moreoptical fibers. The optical fiber elements are typically

individually coated with plastic layers and contained in a protective tube suitable for the environment where the cable will

be deployed.

An optical fiber is a flexible, transparent fiber made of very pure glass (silica) not much wider than a human hair that

acts as awaveguide, or "light pipe", to transmit light between the two ends of the fiber Optical fibers are widely used

infiber-optic communications, which permits transmission over longer distances and at higherbandwidths(data rates)

than other forms of communication. Fibers are used instead of metal wires because signals travel along them with

lesslossand are also immune toelectromagnetic interference.

Optical fiber typically consists of a transparentcoresurrounded by a transparentcladdingmaterial with a lowerindex of

refraction. Light is kept in the core bytotal internal reflection. This causes the fiber to act as awaveguide. Fibers that

support many propagation paths ortransverse modesare calledmulti-mode fibers(MMF), while those that only support a

single mode are calledsingle-mode fibers(SMF). Multi-mode fibers generally have a larger core diameter, and are used

for short-distance communication links and for applications where high power must be transmitted. Single-mode fibers

are used for most communication links longer than 1,050 meters (3,440 ft).

MMF can have maximum segment length of 2kms and supports maximum bandwidth of 100 Mbps.

SMF can have maximum segment length of 100kms and supports maximum bandwidth of 2Gbps.
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