Grob Basic Electronics Book Review

GROB BASIC ELECTRONICS

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CONTENTS

CHAPTER I: ELECTRICITY

An invisible force that can produce heat, light, and motion. Electricity

The force for _________ is an attraction or repulsion between electric charges.

Motion

The basic form for a quantity of electricity. Electric Charge

The closed path for the movement of charges. Circuit

NEGATIVE AND POSITIVE POLARITIES

Two basic particles of electric charge. Electron and Proton

_______ is the smallest amount of electric charge having the characteristic called negative polarity.

Electron

The proton is a basic particle with ________. Positive Polarity

Is it true or false that the neutral condition means equal positive and negative charges?

True

ELECTRONS AND PROTONS IN THE ATOM

The smallest particle of the basic elements that form solid, liquids, gases we know as physical substances.

Atom

Central mass of an atom Nucleus

Proton is _______ times heavier than an electron. 1840

Electrons that can move freely from one atom to the next. Free electrons

Electrons that can move easily from atom to atom in a material. Conductor

The best conductor. Silver

A material with atoms in which the electrons tend to stay in their own orbits.

Insulator

An insulating material and also can store electric charges. Dielectric

A material that conducts less than the metal conductors but more than the insulators.

Semiconductors

Practically all transistors are made of _________. Silicon

Defined as a substance that cannot be decomposed any further by chemical action.

Elements

Greek word that means a particle too small to be subdivided. Atom

Semiconductors have _____ electrons in the outermost ring. 4

____ Electrons in the outside ring is a stable structure. 8

A group of two or more atoms. Molecule

A group of two or more elements. Compound

The smallest unit of a compound with the same chemical characteristics. Molecule

Atomic number of oxygen. 8

CHAPTER 2 : RESISTORS

INTRODUCTION

The most often used construction of a resistor. Carbon-composition

type


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The purpose of using a resistor in a circuit is to reduce __________ to a specific value.

Current (I)

True or false: the resistance has a common effect for DC and AC circuits. True

TYPES OF RESISTORS

Two main characteristics of a resistor. Resistance and its

power rating

It means the power is wasted. Dissipation

The power rating of carbon resistors. 1W or less

Resistors with higher resistance values usually have lower wattage ratings because __________.

They have less current

True or false: the lower the power rating, the smaller the physical size of the resistor.

True

A type of resistor that has a special type of wire called resistance wire. Wire-wound Resistor

The power rating available in small wire-wound resistors. 3 to 4W

This type of resistor is made of finely divided carbon or graphite mixed with a powdered insulating material.

Carbon-composition

Resistor

These are metal caps with leads of tinned copper wire of resistor for soldering the connection into circuit.

Axial leads

Available values of carbon resistors. 1 to 20Ω

The power rating of carbon resistor. 0.1 to 2W

Two kinds of film-type resistors. Carbon film type and

Metal-film

This type of resistor has a carbon coating fired onto a solid ceramic substrate.

Chip resistors

This type of resistor is a wire-wound resistor made to burn open easily when the power rating is exceeded. It then serves the dual functions of a fuse and a resistor to limit the current.

Fusible resistors

RESISTOR COLOR CODING

The organization standardized the color coding of resistor. Electronic Industries

Association (EIA)

In reading the resistor color coding value, the first band close to the edge gives ______.

The first digit in the

numerical value of

resistor.

In reading the resistor color coding value, the third band indicates ______. The decimal multiplier.

The amount by which the resistor can be different from the color-coded value.

Tolerance

The typical tolerance of wire-wound resistor. ±5%

The typical tolerance of precision wire-wound resistor. ±1% or less

VARIABLE RESISTORS

It can be wire-wound or carbon-type resistor. Variable Resistor

The way resistor varies with the shaft control. Taper of the control

It is convenient unit for providing any one resistor within a wide range of values.

Decade box

RHEOSTATS AND POTENTIOMETERS

It is a variable resistor with two terminals connected in series with a load. Rheostat


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The purpose is to vary the amount of current.

It is generally called pot and it has three terminals. Potentiometer

These are generally wire-wound high-wattage resistors for power applications.

Commercial rheostats

POWER RATING OF RESISTORS

A resistor should have _________ to dissipate the power produced by the current flowing through the resistance, without becoming too hot.

High wattage rating

A type of resistor that operates at high temperature, a typical value being 300°C for the maximum temperature.

Wire wound resistor

SERIES AND PARALLEL COMBINATIONS OF RESISTORS

Two equal resistors in ________ double the resistance. Series

Two equal resistors in ________ have one-half the resistance. Parallel

RESISTORS TROUBLES

When the open resistor is a series component, ____________. There is no current in

the entire series path.

These are preferred in applications such as volume and tone controls because the smoother change in resistance results in less noise when the variable arm is rotated.

Carbon controls

Resistance measurements are made with a _____________. Ohmmeter

A ____________ resistor reads infinitely high ohms. Open

A resistor can change in value beyond it tolerance caused by __________. Heat over a long period

of time

CHAPTER 3 : OHM’s LAW

INTRODUCTION

He discovered the Ohm’s Law. Georg Simon Ohm

It is used to determine the amount of electric power in the circuit. Ohm’s Law

True or false: Ohm’s law applies to both DC and AC circuits. True

PRACTICAL UNITS

It is the amount of current through a one-ohm resistance that has one volt of potential difference applied across it.

One ampere

It is the potential difference across a one-ohm resistance that has one ampere of current through it.

One volt

It is the amount of opposition in a resistance that has a V/I ratio of 1, allowing one ampere of current with one volt applied.

One ohm

LINEAR PROPORTION BETWEEN V AND I

The formula which states that V and I are directly proportional for any value of R.

Ohm’s Law

In ohm’s law, increases of volts will __________ the current. Increase


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It shows how much current the resistor allows for different voltages. Volt-ampere

characteristic graph

In a volt-ampere characteristic graph, the value in y axis or ordinate is _______________.

Current values

In a volt-ampere characteristic graph, the value in x axis or abscissa is _____________.

Voltage values

In ohm’s law, voltage and current are __________. Directly proportional

This type has a nonlinear volt-ampere characteristic. Nonlinear resistance

Whether the resistor is linear is not, the current is ________ for more resistance, with applied voltage constant.

Less

ELECTRIC POWER

The unit of electric power. Watt

He discovers the unit of electric power. James Watt (1736-1819)

It equals the work done in one second by one volt of potential difference in moving one coulomb of charge.

One watt of power

It is the time rate of doing work. Power

It is the time rate at which charges is forced to move by voltage. Electric power

1 horse power is equal to____________. 764 Watts or 550 ft lb/s

One horse power is approximately equal to ____________. ¾ kW

It is the power used during a period of time. Work

One joule is equal to ________ 1watt second

One watt is equal to ___________. 1 joule/second

One joule is equal to ________ coulomb 6.25 x 1018

eV

This is a unit commonly for large amounts of electrical work or energy. Kilowatt-hour

The amount is calculated simply as the product of the power in kilowatts multiplied by the time in hours during which the power is used.

Kilowatt-hour

ELECTRIC SHOCK

It is a sudden involuntary contraction of the muscles, with a feeling of pain, caused by current through the body. It can be fatal.

Shock

The greatest shock hazard is from ______ that can supply appreciable amounts of power.

High-voltage circuits

The value of “let go” current for men. 9mA

The value of “let go” current for women. 6mA

The greatest danger of shock is form a source having an output of ________ with enough power to maintain the load current through the body when it is connected across the applied voltage.

More than 30 V

CHAPTER 4 : SERIES CIRCUITS

INTRODUCTION

The purpose of this circuit is to connect different components that need the same current.

Series Circuits


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WHY I IS THE SAME IN ALL PARTS OF A SERIES CIRCUIT

It is a movement of charges between two points, produced by the applied voltage.

Electric Current

The order in which components are connected in series does not affect the ___________.

Current

It is the same amount at the same time in all series components. Current

The free electrons moving away from one point are continuously replaced by free electrons flowing from a ____________ in the series circuit.

Adjacent Point

POLARITY OF IR VOLTAGE DROPS

When an IR voltage drop exists across a resistance, one end must be either ________________ than the other end.

More positive or more

negative

The polarity of IR voltage can be associated with the direction of ___________.

Current through a

resistor

The top end of R in the diagrams is _______. Negative

True or false: The resistor does not know which direction of current we are thinking of.

True

TOTAL POWER IN A SERIES CIRCUIT

The power needed to produce current in each series resistor is used up in the form of __________.

Heat

It is the sum of the individual values of power dissipated in each part of the circuit.

Total Power

SERIES-AIDING AND SERIES OPPOSING VOLTAGES

These are connected with polarities that allow current in the same direction. Series-aiding Voltages

Voltages are connected ______ when the plus terminal of one is connected to the negative terminal of the text.

Series-aiding

Voltages are connected ______ when the negative terminal of one is connected to the negative terminal of the text.

Series-opposing

If the series-opposing voltages are equal, the net voltage is equal to __________.

Zero

ANALYZING SERIES CIRCUITS

We must know the _________ to calculate current because the total applied voltage is given.

Total Resistance

A common application of series circuits is to use a resistance to ______ the voltage from the source to a lower value.

Drop

EFFECT OF AN OPEN CIRCUIT IN A SERIES PATH

It is break in the current path. Open Circuit

The resistance of the _________ is very high because an insulator like air takes place conducting path of the circuit.

Open path


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With an open in any part of a series circuit, the current is _____ in the entire circuit.

Zero

Each of the resistors in the open circuit has an IR drop of ______. Zero

There is ___________ with the open circuit because there is no complete path outside the battery between its two terminals.

No Current

The __________ have the entire applied voltage indicates a good way to find an open component in a series string.

Open Terminals

CHAPTER 5 : PARALLEL CIRCUITS

INTRODUCTION

There have one common voltage across all the branches but separate branch currents that can be different.

Parallel Circuits

It is formed when two or more components are connected across one voltage source.

Parallel Circuits

THE APPLIED VO LTAGE VA IS THE SAME ACROSS PARALLEL BRANCHES

The typical application of parallel circuits. Typical House Wiring

It is formed when two or more components are connected across one voltage source.

Parallel Circuits

ANALYZING PARALLEL CIRCUITS

When you know the voltage across one branch, this voltage is __________. Across all the branches

If you know IT and one of the branch currents I1, you can find I2 by _______________.

Subtracting I1 from IT

EFFECT OF AN OPEN BRANCH IN PARALLEL CIRCUITS

An open in any circuit is a ____________ that results in no current. Infinite Resistance

In parallel circuits, open circuits in one branch results ___________, but in other branches can have their normal current.

No current through

that branch

EFFECT OF A SHORT CIRCUIT ACROSS PARALLEL BRANCHES

In parallel circuits, a short circuit has _________, resulting in excessive current.

Zero Resistance

In parallel circuits, when one branch is short-circuited, __________. All the parallel paths

are also short-circuited.

PARALLEL CIRCUIT FOR THE OR LOGIC FUNCTION

The __________ function corresponds to switches in parallel. OR Gate


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CHAPTER 6 : SERIES – PARALLEL CIRCUITS

INTRODUCTION

It is used when it is necessary to provide different amounts of voltage and current for the components using one source of applied voltage.

Series-Parallel Circuit

RESISTANCE STRINGS IN PARALLEL

In series-parallel circuits, with too low a _________, there would be insufficient current for normal operation and the bulbs would not operate at normal brilliance.

Voltage

Each branch current equals the voltage applied across the branch divided by __________

The total resistance in

the branch.

For any one resistance in a string, the current in the string multiplied by the resistance equals the ___________ across that particular resistance.

IR Voltage Drop

It is equal to the sum of the branch currents for all parallel strings. Total line current

It is equal to the applied voltage divided by the total line current. Resistance of the total

series-parallel circuit

The series parts have the same _________. Current

The parallel parts have the same __________. Voltage

ANALYZING SERIES-PARALLEL CIRCUITS

With parallel string across the main line, the branch currents and total current can be found without _______.

Total Resistance

When parallel strings have series resistance in the main line, ______ must be calculated to find IT, assuming no branch current is known.

Total Resistance

It is applied across the RT of the entire circuit, producing an IT that flows only in the main line.

Source Voltage

Any individual series resistance has its own IR drop that must be _____ the total VT.

Less than

WHEATSTONE BRIDGE

It has four terminals, two for input voltage and two for output. Bridge Circuit

Inventor of the Wheatstone Bridge Sir Charles Wheatstone

(1802 – 1875)

In this circuit, an unknown resistance is balanced against a standard accurate resistor for precise measurement of resistance.

Wheatstone Bridge

It can be analyzed as simply series resistance strings in parallel when the current is zero through the meter.

Balanced Bridge

Circuit

CHASSIS – GROUND CONNECTIONS

It is usually made by driving copper rods into the ground and connecting the ground wire of the electrical system to these rods.

Ground Connection

A chassis ground in which connected to earth ground. Cold side or low side

A chassis ground in which not connected to earth ground. Hot side or High side


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VOLTAGES MEASURED TO CHASSIS GROUND

When a circuit has the chassis as a common return, we generally measure the voltages with respect to ___________.

Chassis

The negative side of total voltage is grounded. Positive voltages to

negative ground

The voltage source is inverted. Any point in the circuit must be more negative than the positive terminal of the source, even when this terminal is grounded.

Negative Voltages to

Positive Ground

CHAPTER 7 : VOLTAGE AND CURRENT DIVIDERS

INTRODUCTION

It gives the series voltages even when the current is not known. Voltage Division

Formula

It gives the branch currents even when the branch voltage is not known. Current Division

Formula

CURRENT DIVISION BY PARALLEL CONDUCTANCES

If conductance is the reciprocal of resistance, therefore, conductance and current are ____________ proportional.

Directly

The method of _______ is usually easier to use than the method of resistances from three or more branches.

Conductance

SERIES VOLTAGE DIVIDER WITH PARALLEL LOAD CURRENT

It is often used to tap off part of the applied voltage VT for a load that needs less voltage than VT.

Voltage divider

All the current in the circuit must come from the _______. Source Voltage

It is a steady drain of the source. Bleeder Current

DESIGN OF A LOADED VOLTAGE DIVIDER

This type of circuit is used for the output of a power supply in electronic equipment to supply different voltages at the taps, with different load currents.

Loaded Voltage Divider


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CHAPTER 8: DIRECT CURRENT METERS

INTRODUCTION

Meters with values printed on a scale and moving a pointer that indicates values on the scale.

Analog meters

Meters with numerical readouts that indicates values directly. Digital meters

To measure voltage, the test leads of the voltmeter are connected in __________ across two points of potential difference.

Parallel

To measure currents in units of amperes, milli-amperes, or micro-amperes, the meter is a __________ component in the circuit.

Series

A combinational meter, like the VOM and DMM will all three functions. Multimeter or

multitester

MOVING COIL METER

It can be used to measure voltage or resistance. Volt-ohm-milli-ammeter

It is generally used in a VOM in which the construction consists essentially of a coil of fine wire on a drum mounted between the poles of a permanent magnet.

Moving coil meter

It is directly proportional to the amount of current in the coil. Pointer deflection

It is an extremely sensitive instrument for measuring very small values of current.

Galvanometer

It is used for reading the value of a small momentary current, to measure electric charge.

Ballistic galvanometer

The moving coil arrangement is often called a ___________, after its inventor, who patented this meter movement in 1881.

D’Arsonval Movement

The optical error caused by looking at the meter from the side. Parallax error

The meter movement can be constructed with moving coil and pointer suspended by a metal band, instead of the pivot and jewel design with a restoring spring.

Taut-band meters

VOLTMETERS

It is commonly used for measuring voltage by the addition of a high resistance series with the movement.

Voltmeter

The series resistance must be _________ than the coil resistance in order to limit the current through the coil.

Higher

It is a series resistor usually connected inside the voltmeter case. Multiplier

Since a voltmeter has high resistance, it must be connected in ______________ to measure the potential difference across two points in a circuit.

Parallel

The ohms-per-volt rating is also called ___________ of the voltmeter. Sensitivity

OHMMETERS

It consists of an internal battery, meter movement, a current-linking resistance.

Ohmmeter


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For measuring resistance, the ohmmeter leads are connected across the __________ to be measured.

External resistance

Typical resistance of series ohmmeter circuit. 1500Ω

When the ohmmeter leads are open, not touching each other, the current is _________.

Zero

The arrangement of the ohms scale increases from left to right. Back-off scale

A symbol which means that the measured resistance is infinitely greater than the ohmmeter resistance.

Lazy eight or “∞”

It is given for each ohms range because the highest resistance is infinite on all the ohms ranges.

Multiplying factor

For higher values of external resistance, the meter current _________ to indicate higher resistances on the back-off ohms scale.

Decreases

To compensate for lower voltage output as the internal battery ages, an ohmmeter includes a ____________ to calibrate the ohms scale.

Variable resistor

A back-off ohmmeter is always adjusted for __________. Zero ohms

MULTIMETERS

It is use to measure voltage, current, or resistance. Multimeter

The main types of Multimeters VOM and DMM

Most analog Multimeters have an AC voltage scale calibrated in _________ for measuring AC signals.

Decibels (dB)

It is a logarithmic unit used for comparisons of power levels or voltage levels.

Decibels (dB)

Positive decibel values, above the zero mark, indicate AC voltages above the reference of ___________.

0.775 V

It is a probe with a clamp that fits around the current-carrying wire in which its magnetic field is used to indicate the amount of current.

Amp-clamp probe

The accessory probe that can be used with a multimeter to measure DC voltages up to 30kV. The probe is basically just an external multiplier resistance for the DC voltmeter.

High-voltage probe

DIGITAL MULTIMETERS

This type of test instrument has become very popular because the digital value of the measurement is displayed automatically with decimal point, polarity, and the unit for voltage, ampere, or ohms.

Digital multimeter

These are generally easier to use because they eliminate the human error that often occurs in reading different scales on an analog meter with a pointer.

Digital meters

The basis of the DMM operation is the use of a ____________ circuit. Analog to digital circuit

It is a visual display with decimal values in which generally used to show the values processed by digital circuit.

Liquid-crystal display

(LCD)

The input resistance of the DMM is in the range of _________. 10 to 20MΩ

The DMM has a ____________ that serves as an AC converter. Internal diode rectifier

A DMM ohmmeter usually has an open-circuit voltage across the meter leads of about __________.

0.4V

To measure current in DMM, the ______ provide proportional IR voltage. Internal resistors

It is supplied by the DMM for the diode to test the voltage across it Current


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junction.

For diode test in DMM, the short-circuit junction will read _______. 0V

It enough for practically all measurements made in troubleshooting electronic equipment.

3 ½ digit resolution

It is where the meter automatically shifts to a higher range as soon as an overload is indicated.

Auto-range function

Maximum diode test voltage in DMM. 2V

Maximum DC voltage range of DMM. 1000V

Test frequency used for audio equipment. 400Hz

Test frequency used for power-line equipment. 60Hz

The range of current measurements of DMM. 0 to 320mA

The bar at the bottom of the display is used only to show the relative magnitude of the input compared to the full-scale value of the range in use.

Analog display

CHAPTER 9 : KIRCHOFF’s LAW

INTRODUCTION

The algebraic sum of the voltage sources and IR voltage drops in any closed path must total ________.

Zero

At any point in a circuit the algebraic sum of the currents directed in and out must total ________.

Zero

Creator of Kirchoff’s Law Gustav R. Kirchoff

KIRCHOFF’S CURRENT LAW (KCL)

The algebraic sum of the currents entering and leaving any point in a circuit must equal the algebraic sum of the currents out of that point.

Kirchoff’s Current Law

(KCL)

It means combining positive and negative values. Algebraic Sum

Consider all currents into a branch point as __________ and all current directed away from that point as ____________.

Positive; Negative

It is really the basis for the practical rule in parallel circuits that the total line current must equal the sum of the branch currents.

Kirchoff’s Current Law

(KCL)

KIRCHOFF’S VOLTAGE LAW (KVL)

Go around any closed path and consider any voltage whose negative terminal is reached first as a negative term and any voltage whose positive terminal is reached first as a positive term.

Kirchoff’s Voltage Law

(KVL)

Any closed path is called __________. Loop

The Greek letter which means “sum of”. Sigma “Σ”

When a loop does not have any voltage source, the algebraic sum of the IR voltage drops alone must total ________.

Zero


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CHAPTER 10 : NETWORK THEOEMS

INTRODUCTION

It is just a combination of components, such as resistances interconnected in a way to achieve a particular end result.

Network

It usually provides shorter methods of solving the circuit than the Kirchoff’s law.

Network Theorems

SUPERPOSITION

This theorem is very useful because it extends the use of Ohm’s Law to circuits that have more than one source.

Superposition

In a network with two or more sources, the current or voltage for any components is the algebraic sum of the effects produced by each source acting separately.

Superposition Theorems

Each __________ can have any number of series resistances. Voltage Divider

It means that current is proportional to the applied voltage Linear

It means that the current is the same amount for opposite polarities of the source voltage.

Bilateral

There are components that doesn’t amplify or rectify. Passive components

These are components such as transistors, semiconductors diodes, and electron tubes in which are never bilateral and often are not linear.

Active Components

THEVENIN’S THEOREM

Named after M. L. Thevenin, a French engineer, this theorem is very useful in simplifying the voltages in a network.

Thevenin’s Theorem

It states that the entire network connected to two terminals can be replaced by a single voltage source VTH in series with a single resistance RTH.

Thevenin’s Theorem

It is the open-circuit voltage across terminal. VTH

It is the open-circuit resistance across terminals. RTH

NORTON’S THEOREM

Named after E. L. Norton, a scientist with Bell Telephone Laboratories, this theorem is used for simplifying a network in terms of currents instead of voltages.

Norton’s Theorem

It states that the entire network connected to two terminals can be replaced by a single current source IN in parallel with a single resistance RN.

Norton’s Theorem

It is the resistance looking back from open terminals. RN

Any components directly across the two terminals are also short-circuited by the _________.

Wire Jumper

MILLMAN’S THEOREM

This theorem provides a shortcut for finding the common voltage across any number of parallel branches with different voltage sources.

Millman’s Theorem

This formula is derived from converting the voltage sources to current Net VXY


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sources and combining the results.

CHAPTER 11: CONDUCTORS and INSULATORS

INTRODUCTION

These have a very low resistance. Conductors

Typical value of resistance in copper wire of 10 ft. 0.1Ω

It is used in the manufacture of carbon composition resistors. Carbon

FUNCTION OF THE CONDUCTORS

The resistance of the two 10 – ft lengths of copper wire conductor is ________.

0.08Ω

TYPES OF WIRE CONDUCTORS

Most wire conductors are ________. Copper

It is easier to solder for connections. Tinned Wire

It is flexible, easier to handle and less likely to develop an open break. Stranded Wire

It is often has an insulating coating of enamel or shellac. Very Thin Wire

Hookup that is bare should be enclosed in a hollow insulating sleeve called ___________.

Spaghetti

Is it used for very low resistance. Braided conductor

Two or more conductors in a common covering form a ________. Cable

It has 25 conductors but not in pairs. Ribbon Cable

Constant spacing between two conductors through the entire length provides a _____________.

Transmission Line

It is generally used for the signals in cable television. Coaxial Cable

Two conductors are imbedded in plastic to provide constant spacing. This type of line is commonly used in television for connecting the antenna to the receiver.

Twin – Lead Wire

It specifies an opposition to current that can include resistance, inductance and capacitance.

Impedance

It is constant for any length because it depends on the square root of ratio for the inductance in the line to the capacitance between the conductors.

Characteristic

Impedance

For ¼ inch coaxial cable, it s characteristic impedance is approximately _______.

75Ω

For twin lead wire with 3/8 inch spacing, the characteristic impedance is _______.

300Ω

CONNECTORS

It is often used for screw – type materials. Spade Lug

It is commonly used for shielded cables with audio equipment. RCA – type Plug

It is still used in some applications, but in a smaller size. Phone Plug

It is universally used in cable television because of its convenience. F Connector

It has eight wires in a flat, plastic ribbon. Multiple Connector

It is a standard connector for computer equipment. It has 26 pins. RS – 232


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PRINTED WIRING

Most electronic circuits are mounted on a plastic insulating board with printed wiring.

Printed Circuit Board

(PCB)

SWITCHES

These are commonly used to open or close a circuit. Switches

It provides an ON or OFF position for one circuit. Single Pole Single

Throw (SPST)

It provides switching for one side of the circuit. Single Pole Double

Throw (SPDT)

It provides switching for both lines of either of two circuits. Double Pole Double

Throw (DPDT)

It has eight miniature rocker switches. DIP Switch

It is an automatic switch with contacts that can be closed or opened by current in the relay coil.

Relay Switches

FUSES

It is used as a protection against an overload resulting from a short circuit. Fuse

The metal fuse element may be made of __________. Aluminum, tin coated

copper or nickel

This type of fuse has a coiled construction. They are designed to open only on a continued overload.

Slow – Blow Fuse

These have a thermal element in the form of a spring. Circuit Breaker

It is sometimes used as a fuse in television receivers. Short length of bare

wire

It can be mounted between two terminal strips on the chassis. Wire link

CHAPTER 12: BATTERIES

INTRODUCTION

It is a group of cells that generate energy from the internal chemical reaction.

Battery

It consists of two different conducting materials as the electrodes that are immersed in an electrolyte.

Cell

A battery with an output of 1.5v. Carbon zinc dry cell

These are used for all types of portable electronic equipment, photographic equipment and toys.

Dry Battery

It is the type almost always used for automobile batteries. Lead Sulfuric Acid Cell

GENERAL FEATURES OF BATTERIES

It is combination of cells. Battery

It was used to supply enough current to heat the filament for thermoionic emission of electrons from a heated source.

A Battery


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Typical rating of A battery. 4.5 – 6 V with 150mA

or more

It was used for a small negative DC bias voltage at the control grid. C Battery

A battery that has a medium voltage and current ratings B Battery

This type of cell cannot be recharged. Primary Cells

This type of cell can be recharged because the chemical action is reversible. Secondary

Cells

The discharging and recharging of the cell is called _______. Cycling

Secondary can be recharged. Storage Cell

The most common type of secondary cell. Lead Acid Cell

In this type of cell, the electrolyte cannot be spilled and the cell can operate in any position.

Dry Cells

This type is a secondary cell that can be recharged, but it has a sealed electrolyte that cannot be refilled.

Sealed Rechargeable

Cells

THE VOLTAIC CELL

The method of converting chemical energy into electric energy. Voltaic Cell

Voltaic cell is also called a _______, named after Luigi Galvani. Galvanic Cell

It gives relative activity in forming ion charges for some of the chemical elements.

Electromotive Series

CARBON – ZINC DRY CELL

This is probably the most common type of dry cell. It is also called the Leclanche cell.

Carbon – Zinc Dry Cell

It consists of a zinc anode and a manganese dioxide cathode in a moist electrolyte.

Electrochemical System

It is a combination of ammonium chloride and zinc chloride dissolved in water.

Electrolyte

The reaction in which the ammonia releases hydrogen gas which collects around the carbon electrode.

Polarization

Carbon – zinc dry cells are generally designed for an operating temperature of _______.

70°F

ALKALINE CELL

Type of cell which has an alkaline electrolyte. Manganese – Zinc Cell

It consists of a powered zinc anode and a manganese dioxide cathode in an alkaline electrolyte.

Electrochemical System

The outstanding performance of the alkaline cell is due to its _________. Low Internal

Resistance

This type is actually a modified carbon – zinc cell but the electrolyte contains only zinc chloride.

Zinc Chloride Cells

Which is better for heavy duty use; alkaline or zinc chloride type? Alkaline Cell

LITHIUM CELL


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This type is a relatively new primary cell. Lithium Cell

Lithium cell can provide at least _______ more energy than the equivalent carbon zinc cell.

10 times

The sulfur dioxide is kept in a liquid state using a high pressure container and an organic liquid solvent.

Lithium Sulfur Dioxide

LEAD ACID WET CELLS

Where high values of load current are necessary, it is the type most commonly used.

Lead Acid Wet Cells

It is a dilute solution of sulfuric acid. Electrolyte

It is a secondary cell or storage cell, which can be recharged. Lead Acid Wet Cells

It is a combination of hydrogen and sulfate ions. Sulfuric Acid

These are generally rated in terms of how discharge current they can supply for a specified period of time.

Lead Acid Batteries

Typical values of automobile batteries. 100 – 300 AH

It is a ratio comparing the weight of a substance with the weight of water. Specific Gravity

It refers to a method in which the charger and the battery are always connected to each other for supplying current to the load.

Float Charging

ADDITIONAL TYPES OF SECONDARY CELLS

It is a storage cell that can be recharged by reversing the internal chemical reaction.

Secondary Cells

It is the common type of storage cell. Lead Acid Cell

This type is popular because of its ability to deliver high current and to be cycled many times for recharging.

Nickel Cadmium Cell

It is a true storage cell with a reversible chemical reaction for recharging that can be cycled up to 1000 times.

NiCd Cell

Developed by Thomas Edison, this cell was once extensively in industrial truck and railway applications.

Nickel – Iron (Edison)

Cell

This type has been used in limited railway applications. Nickel Zinc Cell

This cell has been under development for use in electric vehicles. Zinc Chlorine

(Hydrate) Cell

This type is under development for commercial energy applications. Lithium Iron Sulfide

Cell

This is another type of cell being developed for electric vehicle applications. The cell is designed to operate at temperature between 550 and 650°F.

Sodium Sulfur Cell

A recent development in battery technology is the rechargeable plastic cell made from a conductive polymer, which is a combination of organic chemical compounds.

Plastic Cell

It consists of an electrolyte between two polymer electrodes. Plastic Cell

This type converts the sun’s light energy direct into electric energy. Solar Cell

CHAPTER 13: MAGNETISM

INTRODUCTION

It is derived from the iron oxide mineral magnetite. Magnetism


17

It refers specifically to the magnetic properties of iron. Ferromagnetism

THE MAGNETIC FIELD

These are the points of concentration of magnetic strength. North and South Poles

The magnet can be considered as the _____ for an external magnetic field, provided by the two opposite poles at the ends.

Generator

These are unaffected by non magnetic materials. Magnetic Field Lines

The end of the magnet bar in which pointed at the North. North-seeking pole

The end of the magnet bar in which pointed at the South. South-seeking pole

A North Pole (N) and a South Poke (S) tend to _________ each other. Attract

A North Pole (N) tends to ________ another North Pole (N), which is also, can apply in the South Pole (S).

Repels

THE MAGNETIC FLUX (Φ)

The entire group of magnetic field lines, which can be considered to flow outward from the North Poke of a magnet.

Magnetic Flux (Φ)

It has more lines of forces and more flux than a weak magnetic field. Strong magnetic field

It is equal to one magnetic field. One Maxwell (Mx)

It can provide a magnetic flux of about 5000Mx. 1-lb of magnet

An important Scottish mathematical physicist who contributed much to the electrical and field theory.

James Clark Maxwell

(1831 – 1879)

It is equal to 1 x 108 lines or maxwells. Weber

The weber unit is named for _________, a German physicist. Wilhelm Weber (1804 –

1890)

This system defines small units. Centimeter-gram-second system (CGS)

This system is for larger units of a more practical size. Meter-kilogram-second

system (MKS)

It provides a worldwide standard in MKS dimensions. System International

(SI)

With magnetic flux, the maxwell is a _______ unit. CGS

The weber is a _________ unit. MKS or SI unit

For science and engineering, the _______ units are preferred values. SI units

FLUX DENSITY (B)

It is the number of magnetic field lines per unit area of a section perpendicular to the direction of flux.

Flux Density (B)

In the CGS system, this unit is one line per square centimeter, or 1 Mx/cm2. Gauss

The unit Gauss is named for ____________, a German mathematician. Karl F. Gauss (1777 –

1855)

As typical values, flux density for the earth’s magnetic field can be about __________.

2G

In SI, the unit of flux density is weber per square meter. One weber per square meter is called ___.

Tesla (T)

The unit tesla is named for ___________, a Yugoslav-born American Inventor in electricity and magnetism.

Nikola Tesla (1857 –

1943)


18

INDUCTION BY THE MAGNETIC FIELD

The electric or magnetic effect of one body on another without any physical contact between them.

Induction

The ability to concentrate magnetic flux. Permeability

The flux density in air. 1G

The relative permeability of the iron core. 200

Typical values of relative permeability for iron and steel. 100 – 9000

AIR GAP OF A MAGNET

The air space between poles of a magnet is its _______. Air Gap

When it is desired to concentrate magnetic lines within a magnet, however, the magnet can be formed as ___________.

Closed Magnetic Loop

It is made in the form of a doughnut. Toroid or Ring Magnet

It is often used for the core. Iron

This type of electromagnet has maximum strength in the iron ring, with little flux outside.

Ring Magnet

The small part of the field in the air. Leakage Flux

The principle of the closed magnetic ring is used to ______. Protect permanent

magnet in storage.

It maintains the strength of the permanent magnet as it becomes magnetized by induction to form a closed loop.

Keeper

TYPES OF MAGNET

It needs current from an external source to maintain its magnetic field. Electromagnet

With this magnet, not only is its magnetic field present without any external current, but the magnet can maintain its strength indefinitely.

Permanent Magnet

With the length much greater than its width, the coil is called ___. Solenoid

It is a switch with contacts that are opened or closed by an electromagnet. Relay

Common application of electromagnet. Magnetic Tape

Recording

These are made of hard magnetic materials, such as cobalt steel, magnetized by induction in the manufacturing process.

Permanent Magnet

A common material of permanent magnet. A commercial alloy of aluminum.

Alnico

It is often used for permanent magnet loudspeakers. Alnico V

A typical size for a steady magnetic field. About 5 lb, with a flux

of 500 – 25,000 lines or

maxwells

The point at which a magnetic material losses its ferromagnetic properties. Curie Temperature

The Curie temperature for iron. 800°C

These include iron, steel, nickel, cobalt, and commercial alloys such as alnico and Permalloy.

Ferromagnetic

Materials

Permeability of the ferromagnetic materials. 50 – 50,000

The relative permeability of Permalloy. 100,000

These include aluminum, platinum, manganese, and chromium. Paramagnetic Materials


19

The permeability of the paramagnetic materials. More than 1

These include bismuth, antimony, copper, zinc, mercury, gold, and silver. Diamagnetic Materials

The permeability of the diamagnetic materials. Less than 1

The basis of all magnetic effects is the __________. Magnetic field

associated with electric

charges in motion.

In terms of molecular structure, iron atoms are grouped in microscopically small arrangements called ____.

Domains

Each domain is an elementary ________, with two opposite poles. Dipole magnet

In crystal form, the iron atoms have domains that are _______ to the axes of the crystal.

Parallel

FERRITES

This is the name for nonmetallic materials that have the ferromagnetic properties of iron.

Ferrites

The ferrites have __________ permeability. Very high

The permeability of ferrites. 50 – 3000

The specific resistance is ________, which makes the ferrite an insulator. 105Ω.cm

A common application of ferrite. Ferrite core in the coils

of RF transformers

It is used in small coils and transformers for signal frequencies up to 20MHz.

Ferrite Core

It is used as a string for one or more beads of ferrite beads. Bare wire

The purpose of this is to reduce the current just for an undesired radio frequency.

choke

MAGNETIC SHIELDING

The idea of preventing one component from affecting another through their common electric or magnetic field.

Shielding

It is best for two shielding functions. Good Conductor

The best shield for a steady magnetic field is a ______________. Good Magnetic

Material of High

Permeability

It is produced by a permanent magnet, a coil with steady direct current, or the earth’s magnetic field.

Steady Field

The shield can be considered as a __________ for the lines of magnetic flux.

Short circuit

THE HALL EFFECT

A small voltage is generated across a conductor carrying current in an external magnetic field.

Hall Effect

The semiconductor material __________ is generally used to produce larger values of Hall voltage.

Indium Arsenide (InAs)

It is directly proportional to the value of flux density. Hall Voltage (VH)

Flux density of InAs. 10kG


20

CHAPTER 14: MAGNETIC UNITS

INTRODUCTION

It is always associated with charges in motion. Magnetic Field

The current supplies a _____________ that increases with the amount of current.

Magnetizing force or

Magneto Motive Force

(mmf)

It produces a flux density that increases with the permeability of the medium.

Field Intensity (H)

AMPERE – TURNS OF MAGNETO MOTIVE FORCE (MMF)

With a coil magnet, the ________ depends on how many current flows in the turns of the coil.

Strength of the

Magnetic Field

The more current, the ___________ the magnetic field Stronger

It specifies the amount of magnetizing force or magnetic potential. Quantity IN

With thinner wire, _______ turns can be used in a given space. More

The CGS unit of mmf is _________. Gilbert (Gb)

An English scientist who investigated the magnetism of the Earth. William Gilbert (1540 –

1603)

One ampere-turn is equal to __________. 1.26 Gb

FIELD INTENSITY (H)

It depends on how long the coil is. Field Intensity (H)

The field intensity for a solenoid is at the ___________. Center of an air core

The field intensity for a iron core is at the ___________. Through the entire core

The CGS unit for H is _________. Oersted (Oe)

A Danish physicist who discovered electromagnetism H. C. Oersted (1777 –

1851)

The unit for field intensity (H). Ampere – turns per

meter

PERMEABILITY (µ)

Using SI units, it is the flux density in webers per square meter. B

It is the absolute permeability, in unit of B/H. Permeability (µ)

The values of relative permeability (µr) must be multiplied by ______ for µo to calculate µ as B/H in SI units.

1.26 x 10-6

B – H MAGNETIZATION CURVE

It is often used to show how much flux density (B) results from increasing the amount of field intensity (H).

B – H Curve

The current in the coil equals to ________. V/R

The __________ of magnetizing force increase with more current. Ampere – turns IN

The field intensity (H) increases with _________. Higher IN


21

The __________ depends on the field intensity (H) and permeability of the iron.

Flux Density (B)

The effects of little change in flux density when the field intensity increases.

Saturation

MAGNETIC HYSTERESIS

It means “a lagging behind”. Hysteresis

The flux ________ the increases or decreases in magnetizing force. Lags

The energy wasted in heat as the molecular dipoles lag the magnetizing force.

Hysteresis Loss

It is actually a B – H curve with an AC magnetizing force. Hysteresis Loop

The value of flux density in which is residual induction of a magnetic material.

Retentivity

The value of -HC, which is equals the magnetizing force that must be applied in the reverse direction to reduce the flux density to zero.

Coercive Force

The method of demagnetization. Degaussing

CHAPTER 15: ELECTROMAGNETIC INDUCTION

INTRODUCTION

He found that current in a wire could move a magnetic compass needle. Oersted

A magnetic field in motion forces electrons to move, producing ___________.

Current

The Henry unit of inductance is named after __________. Joseph Henry

The farad unit of capacitance is named after __________. Michael Faraday

It combines effect of an electric current and magnetism. Electromagnetism

MAGNETIC FIELD AROUND AN ELECTRIC CURRENT

The magnetic lines are ________, as the field is symmetrical with respect to the wire in the center.

Circular

The magnetic field with circular lines of force is in a _____________ to the current in the wire.

Plane Perpendicular

If you look along the wire in the direction of electron flow, the magnetic field is ___________.

Counterclockwise

The opposite direction of electron flow produces a ___________. Reversed Field

When the magnetic lines of two fields are in the same direction, _______________.

The lines of force aid

each other.

With the magnetic lines in opposite directions, ___________. The fields cancel.

MAGNETIC POLARITY OF A COIL

A coil of a wire conductor with more than one turn is generally called _________.

Solenoid

An ideal solenoid has a length much greater than its ___________. Diameter

If the coil is grasped with the fingers of the left hand curled around the coil in the direction of electron flow, the thumb points to the ______________.

North Pole of the coil.


22

It is used here because the current is electron flow. Left Hand Rule

The magnetic polarity depends on the ______________. Direction of the current

and the direction of the winding

It can be over and under, starting from one end of the coil, or under and over with respect to the same starting point.

Direction of winding

INDUCED CURRENT

The action in which the motion of magnetic lines cutting across a conductor forces free electrons in the conductor to move.

Induction

It is the result of generator action as the mechanical work put into moving the magnetic field is converted into electric energy when current flows in the conductor.

Induced Current

When the magnet is moved downward, _____________. Current flows in the

direction shown.

Without motion, there is ________ current No current

It is necessary in order to have the flux lines of the magnetic field cut across the conductor.

Motion

The conductor must be ___________ to make its induced current have an associated magnetic field in the same plane as the external flux.

Perpendicular

The effect of electromagnetic induction is increased where a __________ is used for the conductor.

Coil

LENZ’ LAW

It is simply states that the direction of the induced current must be such that its own magnetic field will oppose the action that produced the induced current.

Lenz’ Law

The direction of the induced current is determined by the ________ for electron flow.

Left – Hand Rule

GENERATING AN INDUCED VOLTAGE

It is an electromotive force (emf), generated by the work of cutting across the flux.

Potential Difference

With a coil, the induced emf is increased by the ___________. Number of turns

The polarity of the induced voltage follows from the direction of ____________.

Induced Current

It represents a voltage source with a potential difference resulting from the separation of charges produced by electromagnetic induction

Induced voltage as a

generator

In a motor, current is applied so that an associated magnetic field can react with the external flux to produce __________

Motion of the

conductor

FARADAY’S LAW OF INDUCED VO LTAGE

The more magnetic lines of force that cut across the conductor, the _________ the amount of induced voltage.

Higher

The more turns in a coil, the ___________ the induced voltage Higher

It is the sum of all individual voltages generated in each turn in series. vind


23

The __________ the flux cuts a conductor, the higher the induced voltage. Faster

The amount of induced voltage can be calculated by ___________. Faraday’s Law

It means a change in the flux φ. dφ

It means a change in time. dt

A smaller value of dφ/dt, results in a _______________. Lower value of induced

voltage.

If the external flux increases, the magnetic field of the induced current will be in the ____________.

Opposite Direction

The induced voltage has the polarity the __________ the change. Opposes

CHAPTER 16: LATERNARING VOLTAGE and CURRENT

INTRODUCTION

The number of cycles per second is the frequency whose unit is ________. Hertz (Hz)

It is equal to one cycle per second. One Hertz

In alternating current, it reverses polarity at a specific rate. Voltage

For either polarity, it varies in amplitude. AC Voltage

ALTERNATING CURRENT APPLICATIONS

It is the reason why AC circuits have so many applications. Characteristics of

Varying Values

The changing magnetic flux of a varying current can produce ____________.

Induced Voltage

It is important with the changing electric field of a varying voltage. Capacitance (C)

VOLTAGE AND CURRENT VALUES FOR A SINE WAVE

It is the maximum value VM or IM.

It applies to either the positive or the negative peak. Peak Value

These values can be used for either current or voltage to define specific magnitudes for comparing one wave with another.

Peak, Average, or RMS

In order to include both peak amplitudes, the _________may be specified. Peak-to-peak Value

This is an arithmetic average of all the values in a sine wave for one alternation, or half-cycle.

Average Value

The most common method of specifying the amount of a sine wave of voltage or current is by relating it to DC voltage and current that will produce the same heating effect.

Root Mean Square or

Effective Value

The advantage of _______ is that is provides a measure based on the ability of the sine wave to produce power.

RMS

The ratio of the RMS to average values. Form Factor

NON-SINUSIODAL AC WAVEFORMS

It is the basic waveform for AC variations for several reasons. Sine Wave

Any waveform that is not sine or cosine wave. Non-Sinusoidal Waveform


24

It is measured between two points having the same amplitude and varying in the same direction.

Cycle

It is measured from the zero axes to the maximum positive or negative value.

Peak Amplitude

The RMS values of 0.707 of maximum apply only to _________. Sine Wave

It is applied only to sine wave, as angular measures are used only for sine waves.

Phase Angles

All the waveforms represent ____________. AC Voltage

It represents a voltage that slowly increases, with a uniform or linear rate of change, to its peak value, and then drops sharply to its starting value.

Sawtooth Wave

Waveform of the sawtooth. Ramp Voltage

HARMONIC FREQUENCIES

Exact multiples of the fundamental frequency. Harmonic Frequencies

These are useful in analyzing distorted sine waves or non-sinusoidal waveforms.

Harmonics

Unit for frequencies multiples which is a range of 2:1. Octave

THE 60 – HZ AC POWER LINE

The 120 V source of commercial electricity is the _________, indicating it is the main line for all the parallel branches.

60Hz Power Lines or

the Mains

The incoming electric service to residences is normally given as ________. 120VRMS

The advantage of AC over DC power is ___________. Greater Efficiency

Frequency of the AC power line in the United States. 60Hz

Frequency of the AC power mains in the England and most European countries is __________.

50Hz

The 60 Hz power line frequency is maintained accurate to _________. ±0.333%

The color coding for the grounded neutral wiring. White

The color coding for the high side wiring Black or Red

The color coding for the grounded wiring Green

The three – wire service with a grounded neutral. Edison System

It is grounded at the service entrance to a water pipe or metal rode driven into the earth.

Neutral Wire

It is the practice of connecting one side of the power line to the earth or ground.

Grounding

It is a device that can sense excessive leakage current and open the circuit as a protection against shock hazard.

Ground – Fault Circuit

Interrupter (GCFI)

MOTORS AND GENERATORS

It converts mechanical energy into electric energy. Generator

It can converts electricity into a rotary motion. Motor

In a generator, it connects to the external circuit to provide the generator output voltage.

Armature

In a motor, it connects to the electrical source that drives the motor. Armature

It is often constructed in the form of a drum, using many conductor loops for increased output.

Armature


25

The rotating armature is the ______ part of the assembly. Rotor

This electromagnet provides the flux cut by the rotor. Field Winding

In a motor, it is produced by the same source that supplies the armature. Field Winding

In a generator, it may be obtained from a separate exciter source. Field Winding

Residual magnetism in the iron yoke of the field allows _________ to start. Self-excited Generator

When the field winding is stationary, it is the ______ part of the assembly. Stator

It enables the rotating loop to be connected to the stationary wire leads for the external circuit.

Slip Rings

These graphite connectors are spring mounted to brush against the spinning rings on the rotor.

Brushes

It converts the AC machine to DC operation. Commutator

The rotor of an inductor motors may be ______ Wire wound or squirrel

caged type

It is constructed with a frame of metal bars. Rotors

This type operates on either alternating or direct current because the field and armature are in series.

Universal Motor

For large power requirements, It is usually a rotating field, while the armature is the stator.

Alternators

THREE – PHASE AC POWER

In an alternator with three generator windings equally spaced around the circle, the windings will produce output voltages _________ with each other.

120° out of phase

The three windings are in the form of a Y also called _______. Wye or Star Connections

CHAPTER 17: INDUCTANCE

INTRODUCTION

It is the ability of a conductor to produce induced voltage when the current varies.

Inductance

Components manufactured to have definite value of inductance are just coils of wires called _________.

Inductors

The unit of inductance. Henry

These are used in RF circuits because higher frequencies need less inductance for the required inductive effect.

Air – Core Coils

These are used in the audio frequency range and for lower frequencies in general.

Iron – Core Inductors

MUTUAL INDUCTANCE LM

When the current in an inductor changes, the varying flux can cut across any other inductor nearby, producing _____ in both inductors.

Induced Voltage

Two coils have ______ of 1H when a current change of 1A/s in one coil induces 1V in the other coil.

Mutual Inductance

Any magnetic lines that do not link the two coils result in ________. Leakage Flux

The fraction of total flux. Coefficient of Coupling


26

A high value of coefficient of coupling Tight Coupling

It allows the current in one coil to induce less voltage in the other coil. Loose Coupling

It increases with higher values for the primary and secondary inductances and tighter coupling.

Mutual Impedance

TRANSFORMERS

It is an important application of mutual inductance. Transformer

The purpose of the transformer is to ________. Transfer primary voltage to the

secondary.

It is used to provide power for the load resistance instead of connecting it directly across the generator, whenever the load requires an AC voltage higher or lower than the generator voltage.

Transformer

The ratio of the number of turns in the primary to the number in the secondary.

Turn Ratio

The ratio of the voltage induced in each turn of the secondary and primary. Voltage Ratio

It is the inverse of the voltage ratio. The voltage step – up in the secondary means current step – down, and vice versa.

Current Ratio

It consists of the one continuous coil with a tapped connection. These are used often because they are compact, efficient, and usually cost less since they have only one winding.

Auto Transformers

The secondary is not connected directly to the AC power line in the primary produces _________.

Reducing the chance of

the electric shock.

It is defined as the ratio of power out to power in. Transformer Efficiency

For the RF transformer, the color code of the output electrode of transistor amplifier.

Blue

For the RF transformer, the color code of the DC supply voltage for this electrode.

Red

For the RF transformer, the color code of the input electrode of next amplifier.

Green

For the RF transformer, the color code of the return line of secondary winding.

Black or White

For the power transformer, the color code of the primary leads without tap. Black

For the power transformer, the color code of the tap on primary Black with Yellow

For the power transformer, the color code of the high voltage secondary to rectifier in power supply.

Red

For the power transformer, the color code of the tap on high voltage secondary.

Red with Yellow

For the power transformer, the color code of the low voltage secondary. Green - Yellow

CORE LOSSES

It flows in a circular path through the cross section of the core. It represents wasted power dissipated as heat in the core.

Eddy Current

It not only isolates the coil from external varying magnetic fields, but also minimizes the effect of the coil’s RF current for external circuits.

RF Shield Cover

It is the result from the additional power needed to reserve the magnetic field in magnetic materials in the presence of alternating current.

Hysteresis Losses


27

It is limited to low values in the microhenry or millihenry range. Inductance for small

coils with an air core

TYPES OF CORE

The purpose of _______ is to reduce the amount of eddy currents. Core

It is a shell-type core formed with a group of individual laminations. Laminated Core

It is generally use to reduce eddy currents in the iron core of an inductance for radio frequencies.

Powdered Iron Core

Powdered iron core consists of individual insulated granules pressed into one solid form called _______.

Slug

It can be for high frequencies with minimum eddy current losses. Ferrite Core

CHAPTER 18: INDUCTIVE REACTANCE

INTRODUCTION

It indicates reactances. X

It is an opposition to current, measured in ohms. Reactance

The amount of XL is equal to _________. 2πfL

HOW XL REDUCES THE AMOUNT OF I

The higher the frequency of the alternating current, the _____ is the XL opposition.

Higher

There is no XL for _________. Steady Direct Current

An inductance can have _______ to reduce the amount of alternating current.

Inductive Reactance

The ________ value depends on the amount of inductance and the frequency of the alternating current.

Inductive Reactance

CHAPTER 19: INDUCTIVE CIRCUITS

INTRODUCTION

It is use as a choke to reduce the current. Coil

SINE WAVE IL LAGS VL BY 90°

It can be measured between any two points having the same value on the iL

and vL values. 90° Difference

Why the phase angle is 90°? Because the vL depends

on the rate of the

change of iL.

XL AND R IN SERIES

When a coil has series resistance, the current is limited by _______. Both XL and R

Voltage VL is _______ with I. 90° out of phase

It just shows the 90° angle without any addition. Phasor


28

IMPEDANCE Z TRIANGLE

A triangle of R and XL in series corresponds to the voltage triangle. Impedance Triangle

The angle between the generator voltage and its current. Phase angle of the

circuit

It is a trigonometric function of any angle, equal to the ratio of the opposite side to the adjacent side of a triangle.

Tangent

The angle that has the tangent equal to ________. 1 - 45°

It specifies the angle’s tangent function as a numerical value. Ratio of XL/R

In a _______ circuit, the higher value of XL compared of R, the more inductive the circuit is.

Series

CHAPTER 26: RESONANCE

INTRODUCTION

The main application of this is in RF circuits for tuning to an AC signal of the desired frequency.

Resonance

It can select a particular frequency for the output, with many different frequencies at the input.

Resonant Circuit

THE RESONANCE EFFECT

It increases as the frequency is increased. Inductive Reactance

It decreases with higher frequencies. Capacitive Reactance

This case of equal and opposite reactances. Resonance

The AC circuit can be called _________. Resonant Circuit

It can be resonant. It all depends on the frequency. LC Circuits

The frequency at which the opposite reactances are equal. Resonant Frequency

In this use, the LC circuit provides maximum voltage output at the resonant frequency, compared with amount at any other frequency either below or above resonance.

Tuning

One of the applications of resonance. Tuning in Radio and Television

SERIES RESONANCE

In a series AC circuit, the inductive reactance _______ by 90°, compared with the zero reference angle of resistance.

Leads

In a series AC circuit, the capacitive reactance _______ by 90°, compared with the zero reference angle of resistance.

Lags

The series resonance should be ______________ for a sharp increase in current at resonance.

As small as possible

The main characteristic of series resonance.

The amount rise of current to its maximum

at the resonant

frequency

Below the resonant frequency, the _________ is small. XL


29

Above the resonant frequency, the ________ is small. XC

At the resonant frequency, __________ are equal. XC and XL

The impedance of the series circuit. Minimum

The current is ____________ at the resonant frequency. Maximum

The current is ____________ with the generator voltage, or the phase voltage of the circuit is 0°.

In phase

The voltage is ____________ across either L or C alone. Maximum

The impendence is __________ at resonant frequency. minimum

PARALLEL RESONANCE

At parallel resonance, the line current is __________. Minimum

At parallel resonance, the impedance is __________. Maximum

The main application of parallel resonance. LC circuit as the load

impedance

At the resonant frequency of 1000 kHz, the line current is at its minimum value of ___________.

0.000133µA

It is at minimum at the resonant frequency. Line Current

The line current is _____________ with the generator voltage, or the phase angle of the circuit is 0°.

In phase

The impedance is ______ at the resonant frequency. Maximum

A parallel resonant LC circuit is called __________. Tank Circuit

The ability of the LC circuit to supply complete sine waves. Flywheel Effect

The process of producing sine waves after a pulse of energy has been applied.

Ringing

CHAPTER 27: FILTERS

INTRODUCTION

It separates different components that are mixed together. Filters

It can separate particles from liquid or small particles from large particles. Mechanical Filter

It can separate different frequency components. Electrical Filter

These are used for filtering. Inductors and Capacitors

Most common filtering applications. Separating audio from

radio frequencies.

DIRECT CURRENT COMBINED WITH ALTERNATING CURRENT

Current that varies in amplitude but does not reverse in polarity. Pulsating or

Fluctuating DC

The effect in which the DC component has been inserted into the AC variations.

DC Insertion

The AC component that consists of the variations above and below the DC axis.

AC Ripple

As a common application, __________ always have fluctuating DC voltage or Current when used from amplifying an AC signal.

Transistor


30

It isolates or blocks steady direct current in the primary. Transformer with a

separate secondary

winding

TRANSFORMER COUPLING

It produces induced secondary voltage just for variations in primary current. Transformer

It corresponds to a steady value of primary current that has a constant magnetic field.

DC Axis

The phase of the AC secondary voltage may be _________, depending on the connections and direction of the windings.

180° opposite

CAPACITOR COUPLING

This method is probably the most common type of coupling in amplifier circuits.

Capacitor Coupling

It means connecting the output of one circuit to the input of the next. Coupling

It is effectively a high pass filter for pulsating direct current. RC Coupling Circuit

It blocks the steady DC voltage but passes the AC component. Capacitance

It is the steady DC component of the input voltage in the RC coupling circuit.

Voltage across CC

In RC coupling circuit, when vin decreases below the average level, __________.

The capacitor loses charge

BYPASS CAPACITORS

It is path around a component. Bypass

These are often used in parallel with resistance to bypass the AC component of a pulsating DC voltage.

Capacitors

FILTER CIRCUITS

It allows the lower frequency components of the applied voltage to develop output voltage across the load resistance.

Low – Pass Filters

It allows the higher frequency components of the applied voltage to develop voltage across the output load resistance.

High – Pass Filters

The case of RC coupling circuit is an example of _________. High – Pass Filters

With higher frequencies in the AC components, ____________. More AC voltage is coupled.

Most common types of filters. L, T, and π

The _____________uses coupling capacitance in series with the load or choke inductance in parallel in the load

High – Pass Filters

The __________ uses inductance in series or bypass capacitance in parallel with the load.

Low – Pass Filters

LOW – PASS FILTERS

The ability to reduce the amplitude of undesired frequencies. Attenuation

The frequency at which the attenuation reduces the output to 70.7 percent response.

Cut – Off Frequency

Frequency lower than the cut – off frequency. Passband


31

Frequency higher than the cut – off frequency. Stopband

A low resistance generator needs the ____________ so that the choke can provide a high series impedance for the bypass capacitor.

T Filter

It is more suitable with a high resistance generator where the input capacitor can be effective as a bypass.

π Filter

Filters that uses only capacitors, inductors, and resistors. Passive Filters

Filters that uses the operational amplifiers (op amp) on an IC chip, with R and C.

Active Filters

HIGH – PASS FILTERS

It passes to the load all frequencies higher than the cutoff frequency. High – Pass Filter

Filter that allows a band of frequencies to be coupled to the load. Bandpass Filter

Its purpose is to have the filter present constant impedance at the input and output terminals.

Constant – K Filter

The design is based on the ratio of the filter cutoff frequency to the frequency of infinite attenuation.

The m-derived Filter

RESONANT FILTERS

It provides a convenient method of filtering a band of radio frequencies. Tuned Circuits

Filters that prevents a band of frequencies from being coupled to the load. Bandstop Filter

In the application of a bandstop filter to suppress certain frequencies, the LC circuit is often called __________.

Wavetrap

It has maximum current and minimum impedance at the resonant frequency.

Series Resonant Circuit

It has maximum impedance at the resonant frequency. Parallel Resonant

Circuit

Filters which uses quartz crystals. Crystal Filters

The characteristic of some crystals in which can be made to vibrate by a voltage input or produce voltage output when it is compressed, expanded, or twisted.

Piezoelectric Effect

Crystal used in crystal filters. Lead Titanate

INTERFERENCE FILTERS

It is a conductor for interfering RF currents produced by motors, fluorescent, lightning circuits, and RF equipments.

Power – Line Filters

Filters that attenuate frequencies below 54MHz, which is lowest frequency for channel 2.

Television Antenna

Filter

CHAPTER 28: ELECTRONIC DEVICES

INTRODUCTION

A group of chemical elements with special electrical characteristic and has a unique atomic structure that allows the addition of specific impurity

Semiconductor


32

elements to produce useful features that can be applied in electronic circuits.

Most common semiconductors. Silicon and Germanium

SEMICONDUCTORS

Materials that are not as good as the metals as electrical conductors but they are not insulators.

Semiconductor

Electron valence of all semiconductor elements. ±4

Atomic number of silicon. 14

A combination of atoms sharing groups of valence electrons. Covalent Bond

All semiconductor devices are ____________, generally using silicon. Solid-State Components

Semiconductor that doesn’t have impurities. Intrinsic

_________ is the common source of silicon.

Silicon Dioxide. Sand

The year where the element silicon was discovered. 1823

The year where the element germanium was discovered. 1886

Germanium is recovered from the ___________. Ash of certain coals

Germanium has only about ________ the resistance of Silicon. 1000

1

The process of adding impurity elements that result in the desired electrical characteristics.

Doping

Doped semiconductor is also called _________. Extrinsic

Semiconductor

Doping elements for N-type. Arsenic, Antimony, or Phosphorus

Doping elements for P-type. Boron, Aluminum,

Gallium, or Indium

The one missing electron in such a covalent bond that is considered as a free positive charge.

Hole

The charge that is same amount as a proton, equal to that of an electron but with opposite polarity.

Hole Charge

Electron flow in P-type semiconductor. Hole Current

When the majority charges are made to move in a semiconductor by an applied voltage, the result is a relatively large amount of ___________.

Forward Current or

Easy Current

Very small current of minority charges. Reverse Current or

Leakage Current

________ is an atom, with it nucleus, where the atom has a net charge, either positive or negative.

Ion

THE PN JUNCTION

_________ provides an internal contact potential, which is 0.7v for silicon and 0.3v for germanium.

PN junction

Width of the PN junction. 10-4 cm

The combination of opposite charge in the PN junction that is neutral. Electron-hole pairs

External voltage of Silicon 0.7 V

External voltage of Germanium 0.3 V


33

The barrier voltage is higher for a ____________ because its lower atomic number allows more stability in the covalent bonds.

Silicon Junction

_________ of the junction is characteristic of the element. Barrier Voltage (Vb)

Because of its neutral electron-hole pairs, the junction area is considered as ____________. It has no free charge carriers that can be moved.

Depletion Zone

Barrier voltage ______ when higher than room temperature is applied. Decreases

Connection of wire conductors without any barrier potential. Ohmic Contact

SEMICONDUCTOR DIODES

A _________ is essentially a PN junction. Diode

The CR stands for ___________ in the schematic diagrams. Crystal Rectifier

________ is the positive side of the diode. Anode

________ is the negative side of the diode. Cathode

This function is converting ac input from the 60Hz power line to dc output. Power-Supply Rectifier

A rectifier that only using one diode. Half-Wave Rectifier

It uses a diode to rectify a modulated signal in order to recover the modulating signal.

Signal Detector

In these circuits, the diode functions as a switch.

It is on when the diode conducts and off without conduction. Digital Logic Gates

Diode that can use for electronic tuning. Capacitive Diode

(Varactor)

Common current for rectifiers. 1 A

The stud mount type of diode generally has ____________. High Current Ratings.

Type of power supply that requires four diodes. Bridge Rectifiers

The PIV rating for popular diode is typically __________. 1000 V

Rating of maximum forward current. 1-25 A

The value that can be used across the diode in reverse polarity, negative at the anode, without disrupting the electrical characteristics of the junction.

Peak Inverse Voltage

(PIV)

PNP AND NPN TRANSISTORS

A component consists of a P or N semiconductor between opposite types. Transistor

The function of emitter in the transistor. Supplies free charges

The function of base in the transistor. Controls the flow of

charges

The function of collector in the transistor. Collects the charges

from the emitter

With the N-type base, the transistor is _________. PNP

Most small transistors are _________ type. NPN

Most small transistors are made of ___________. Silicon

In schematic diagram of transistor, the arrow indicates the flow of current to the __________.

Emitter

In the transistor schematic diagram, if the arrow is pointed to the base, the transistor is _________ type.

PNP

The NPN and PNP types are called __________. Bipolar Junction

Transistors

Three terminals of BJT. Collector, base, emitter

Bipolar junction transistor is a __________ device. Current-controlled


34

With three electrodes, the transistor is considered a _________. Triode

Practically, all __________ in electronics circuits use transistors. Amplifiers

Transistors are the main components in _________. IC chips

The transistor was invented in ______ at Bell Telephone Laboratories. 1948

The name transistor is derived from ________, meaning that it can transfer its internal resistance from low resistor in the emitter-base circuit to a much higher resistor in the collector-base circuit.

Transresistor

This junction has forward voltage applied across the PN or NP junction in order to allow the free charges of the emitter to move into the base.

Emitter-Base Junction

Typically, ________ is a normally off device because it needs forward voltage applied to start conducting.

Junction Transistor

The function of this junction is to remove charges from the base. Collector-Base Junction

Practically, _____ transistors take dc supply voltage at the collector for reverse voltage.

NPN

The typical values of dc supply voltage of transistor depending on the power rating of the transistor.

3-100v

The reverse voltage across the collector-base junction means _________. No majority current

can flow from collector

to base

The ________ has heavy doping to supply free charges. Emitter

The ________ has only light doping and is very thin. Base

The ________ voltage is relatively high. Collector

For typical amplifiers, the actual _________ may have a lower value than the supply voltage because of voltage drops in the circuit.

Electrode Voltage

Typically, _________ or more of the emitter charges provide collector current.

98-99%

It is standard practice to consider _________ into semiconductor as the positive direction of current.

Hole current

For most transistors, ____ is in microamperes or milliamperes. IB

_______ is in milliamperes or in amperes in power transistors. IC and IE

The factor why a transistor can amplify signal input is because the base current controls the _________ current

Collector

The increase of base current means increase of ________. Collector current

To produce current, the emitter-base junction must have at enough ___________.

Forward voltage

For a silicon transistor, the typical values of VBE are _______. 0.5-0.7v

With enough VBE to provide emitter current, the transistor can produce __________.

Amplification

FIELD-EFFECT TRANSISTOR (FET)

This semiconductor device is an amplifier with the same function as a junction transistor.

It is a unipolar device.

Field-Effect Transistor

(FET)

FET input resistance is very high. The typical value is _______. 15MΩ

FET is a ___________ device. Voltage-controlled

Three terminals of FET. Drain, source, and gate

A part of FET that serves as a platform on which the other electrodes are diffused.

Bulk or substrate


35

This is the terminal where the charge carriers enter the channel bar to provide current through the channel.

Source

This is the terminal where current leaves the channel. Drain

This terminal controls the conductance of the channel between the source and drain. The input voltage is generally applied to this terminal.

Gate

Terminals that has no polarity since they are just ohmic contacts. Source and drain

________ Voltage at the gate induces negative charges in the channel. positive

It consists of a metal electrode for the gate separated from the channel by a thin layer of silicon oxide.

Insulated-Gate FET

(IGFET)

In IGFET, _________ is used to apply a voltage to the gate to induce charges in the channel.

Electrostatic induction

Two type of IGFET. Depletion and enhancement mode

The depletion type of IGFET is a normally _____-device. On

In EIA, IGFET depletion-enhancement type C requires _______. Positive gate bias

In EIA, IGFET depletion-enhancement type A takes _______for a middle value of drain current.

Negative gate bias

In EIA, IGFET depletion-enhancement type B can operate with _______. Zero gate current

JFET means ___________. Junction Field-Effect

Transistor

THYRISTORS

This name is a general term for semiconductor devices like the silicon controlled rectifier and the triac often used for power-control circuits.

A solid-state electronic switch for high values of current in the range of amperes.

Thyristors

The name thyristor comes from an older device called a _________, which is a gas-filled tube formerly used for similar applications.

Thyratron

The thyristor is a __________ device. PNPN

Reverse voltage at any junction of thyristor prevents _________ between the two end terminals

Forward current

It is a power rectifier device that needs a forward gate voltage to start conduction. It is considered as a reverse-blocking triode thyristor.

Silicon Controller

Rectifier (SCR)

Terminals of SCR. Anode, cathode, and gate

Typical values for the gate electrode of SCR. 1-3V

Typical value of gate current of SCR. 10-20mA

The minimum value of anode current needed to sustain conduction. Holding Current

The value needed to switch the anode circuit on from the off condition. Latching Current

The latching current is typically _______ times more than the holding current.

Three

The thyristor device which is equivalent to a bidirectional SCR. Triac

The triac can supply power to the load for both _________. Half-cycles of the AC

input

This thyristor is a two-terminal device without a gate electrode. It is used as a bidirectional trigger diode.

Diac

The typical value of firing potential of the diac. 30V


36

True or false, unijunction transistor not a transistor amplifier. True

A negative resistance characteristic of UJT means that the current _________ with less voltage.

Increases

The power rating of UJT is __________. Less than 1 W.

The name ______________ is sometimes used for UJT. Double-base diode

Maximum emitter current of UJT is ______. 8-20mA

SEMICONDUCTOR TYPE NUMBERS AND CASE STYLES

In EIA, the letter __ indicates a semiconductor device. N

In JIS, the letter __ indicates a semiconductor device. S

The semiconductor packaging is standardized by _________. Joint Electronic Device

Engineering Council

(JEDEC)

Case styles labeled TO is for ________. Transistor outline

____________ is a metal chassis or any metal structure that conducts heat away from the transistor.

Heat sink

True or false, transistor gets hot in normal operation from the collector current.

True

The ______ package is for the high-power applications. TO-3

Typically, small-signal transistors generally have a maximum power dissipation of ____________.

200 to 800 mW

Small-signal transistors have a collector current of ____. 1-50 mA

Package case of medium-power transistor. TO-5

Typical power rating of medium-power transistor. 5W

Typical collector current rating of medium-power transistor. 2A

Typical power rating of TO-220 transistor. 10W

Typical collector current rating of TO-220 transistor. 4A

Typical power rating of TO-3 transistor. 25-100 W

Typical collector current rating of TO-3 transistor. 5 A

SPECIAL-PURPOSE DIODES

A semiconductor diode is just a _________. PN Junction

The main use of semiconductor diode. Rectification

This semiconductor device is also called a capacitive diode. Varactor

With reverse voltage of the varactor, the _________ enables the junction to serve as a capacitance because of the separated charges in the depletion zone.

Barrier Voltage

The capacitance values in the varactor are in _______ range. Pico farad

The amount of _______ of the varactor can be controlled by varying the reverse voltage.

Capacitance

The __________ is negative at then anode of the varactor. Reverse voltage

The __________ determines the oscillator frequency of the varactor. LC tuned circuit

Across the tuned circuit, that varactor provides ________ as part of capacitance that determines the resonant frequency.

Capacitance (CV)

Also known as the voltage-reference diode. Zener Diode

The name Zener diode is named after __________, who analyzed the voltage breakdown of insulators.

C.A. Zener


37

Typical reverse breakdown voltage of the Zener diode. 3 to 100 V

In a Zener diode, the __________ is constant as a reference value that can be used for voltage regulation.

Voltage

The name ____________ is also used for a Zener diode. Avalanche Diode

Another term for a tunnel diode. Esaki Diode

___________ can cause a tunneling effect of charge carriers through the depletion zone at junction.

Heavy doping

__________ is a low-power device for microwave frequencies, with relative freedom from radiation effects.

Tunnel diode

For best efficiency for LED, special compounds of __________ are used. Gallium (Ga)

In Light-emitting diodes, a ________ radiates light when current passes through the unit.

PN junction

Type of voltage used in LED. Forward Voltage

Typical voltage value of LED to produce a forward current 1.6 V

Typical value of forward current of LED. 20mA

These are made of a photosensitive material, where the resistance decreases with more light.

Photocells

Material used in photocells. Sulfide

The resistance without light. Dark Resistance

Typically range of the dark resistance. Mega ohms

VISUAL CHARACTER DISPLAYS

The ________________ has more elements of display than the seven-segment display device.

Dot Matrix

The __________ is displayed by having all seven segments lit. Digit 8

The _________ uses a combination of five columns of dots vertically with seven horizontal rows.

Dot Matrix Display

In dot matrix, how many combinations of dots can be lit? 35

The complete assortment of characters is called _______. Font

The type of package of seven-segment display. DIP package

The __________ display uses thin filaments for each segment, similar to those in regular light bulbs.

Incandescent

The display that requires relatively high voltage and emits orange glow. Gas-discharge Tube

The __________ display gives off a greenish glow and operates at lower voltages.

Fluorescent

The very common display which is usually has a red glow. Light-emitting diode

Display

The newer display that creates black characters on a silver background. Liquid Crystal Display

In actual applications, IC units called _________ are used to activate the segments for desired number.

Decoder/drivers

The ____ is formed when segments a, b, and c are lit in LED display. 7

Segments on the LCD are driven by ___________. Low-frequency AC

signals

True or false, direct current must be used to LCD. False, it must not use cause it will damage

them.


38

VACUUM TUBES

A ________ has a glass envelope enclosing metal electrodes in a vacuum. Vacuum Tube

A ________ is heated to emit electrons. Cathode

A ________ is a two-terminal device, since the heater connections are not considered as electrodes.

Diode Tube

In diode tube, the _________ is connected to a power source to heat the cathode to a high temperature, which emits electrons.

Heater or filament

A ________ has three electrodes: cathode, plate, and control-grid electrode. Triode Tube

The _____ is a fine metal wire wrapped around two supports placed in the space between the cathode and anode. It connected to a base pin so that its voltage determines how many electrons can travel from the cathode to the plate.

Control Grid

For small triode amplifier tubes, typical values of positive plate voltage are ______.

90 to 300 V

This tube has an additional grid, resulting in four electrodes. Tetrode

The ___________ purpose is to screen the plate from the control gird, in order to reduce the amount of capacitance between the two electrodes.

Screen Grid

The screen grid must have _________ applied. Positive DC voltage

This tube has one more electrode which is placed between the plate and the screen grid.

Pentode

The _________ purpose is to suppress secondary emission form the plate. Suppressor Grid

TESTING DIODES , TRANSISTORS , AND THYRISTORS

It can be used to check either for an open circuit or a short circuit. Ohmmeter

In an ohmmeter, short indicated practically in ________. Zero Ohms

In an ohmmeter, open circuit indicated practically in ________. Infinite Ohms

When the ratio of reverse to forward resistance is _______, the diode is probably good.

Very High

When both the forward and reverse resistances are very low, close to zero, the diode junction is ___________.

Short Circuit

When _____________ are very high, close to infinite, the diode probably has an open at the terminal.

Forward and reverse resistance

When the forward voltage for VBE is 0.6 to 0.7 V, the transistor is _________.

Silicon

When the forward voltage for VBE is 0.2 to 0.3 V, the transistor is _________.

Germanium

CHAPTER 29: ELECTRONIC CIRCUITS

INTRODUCTION

Two common types of semiconductor devices that make it possible to have so many applications of electronics.

Transistor and Diodes

One of the main applications of transistors. Amplifier Circuit


39

A device that increases the magnitude or amplitude of signal variations to make the desired signal stronger.

Amplifier

_________ combines transistors and diodes in one unit. Integrated Circuit (IC) chip

Transistor or diode that not in an IC chip because the part is complete itself. Discrete Component

ANALOG AND DIGITAL SIGNALS

__________ consists mainly of amplifiers for voltage or current variations that are smooth and continuous.

Analog Circuits

__________ provide electronic switching of voltage pulses. Digital Circuits

The analog form is generally called a ________ type of IC unit because analog information deals with proportional values.

Linear

The ________ in electronic circuits are changes in voltage and current that corresponds to the desired information.

Signal

The electrical variations have a direct relation to the changes that represent the information.

Analog Signal

A _________ consists of a train of pulses for the voltage or current. Digital Signal

The pulse in digital signal is called ___________. Bit

Group of bits is called ___________. Word

A word can have up to _______ bits. 32

An 8-bit word is called __________. byte

AMPLIFIER GAIN

An amplifier circuit has ability to _________ the amount of signal. Increase

Defined as the ratio of output signal to input signal. Measurement of amplifier circuit.

Gain

___________ is a general form of symbol of amplifier. Triangle

Typical values of voltage gain for transistor amplifier circuits. 10 to 2000

The amplifier can be considered as a _________ circuit because it can reverse the polarity of the signal.

Inverter

It is more important in amplifier is the ________ of the output signal. Current Gain

True or false: there are no units for current gain it is a ratio of the same two units of current.

True

Typical values of current gain with transistors. 1 to 500

The product of the voltage gain times the current gain. Power Gain

A high value of power gain for an amplifier means _________. It can drive a load that

requires appreciable

voltage and current

True of False: IC chips have higher power rating than discrete transistor. False, discrete is higher

than the IC chip

Each amplifier circuit with one transistor is called ________. Stage

When the output terminal of one stage drives the input terminal of the next stage, the two stages are connected in __________.

Cascade

In amplifier stages that are in cascaded form, the total gain is __________. Multiplied


40

CHARACTERISTICS OF AMPLIFIER CIRCUITS

Transistors are called a _________ because it can amplify the signal. Active device

Resistors, inductors, and capacitors are considered _________. Passive device

The ________ reduces the amount of current. Resistance

Resistance provides a __________ which is equal to IR. Voltage drop

A ________ can charge and discharge with changes in voltage. Capacitor

Capacitive reactance _________ for higher frequencies. Decreases

Capacitor is practically an __________ circuit. Open

The functions of capacitors in amplifier circuits are;

To block dc voltage,

couple ac signal, and

bypass the ac signal around the components

Typical value that is commonly used for a coupling or bypass capacitor in audio amplifiers.

5µF

Typical value that is commonly used for RF circuits. 100pF

A ___________ allows direct current with dc voltage applied. Inductor

The amount of inductive reactance _______ with higher frequencies and more inductive.

Increases

Inductors are used where it is desired to have _________ for alternating current.

High impedance

Both inductor and capacitor can be used in _________. Resonant circuits

The range of audio frequency. 20 to 20,000 Hz

The frequency range for high-fidelity audio equipment. 50 to 15,000 Hz

The range of audio frequencies in telephone. 100 to 3,000 Hz

Four bands that included in RF range. MF, HF, VHF, and

UHF

Range of AM radio broadcast service. 635 to 1605 kHz

Range of FM commercial radio service. 88 to 108 MHz

Range of TV broadcast stations. 6 MHz

RF amplifiers are usually tuned with _______ resonant at the desired frequency.

LC circuits

A ___________ is a special case for amplifying audio and radio frequencies.

Wideband Amplifier

The amount of gain in a tuned RF amplifier is its ________. Sensitivity

__________ is how narrow the response is in terms of the band of frequencies that are amplified.

Selectivity

OSCILLATORS

The process of ________ means that variations in amplitude are repeated continuously at a specific frequency.

Oscillation

A mechanical example of oscillation. Swinging Pendulum

A ___________ generates ac signal output without any AC signal input from an external source. It is an AC generator for audio or radio frequencies.

Oscillator

True or false: the oscillator output can generate without using energy. False, it cannot generate

The _________ means that the AC signal for oscillator feedback must be in Positive polarity


41

the same phase that an AC input signal would have for amplification.

The ________ results from the two phase reversals of 180° each. Positive feedback

This type of circuit uses a tuning circuit and amplifier which provide feedback.

Tuned RF feedback

Oscillators

The tuned circuit is often called a ________ because it stores energy. Tank Circuit

In the oscillator circuit, the capacitor is the tuning capacitor which is use to _________.

Set the frequency of the

oscillator output.

These are named for the inventors of the two main types of circuits for an RF feedback oscillator.

Hartley and Colpitts

Oscillators

In this type of circuit, the feedback is provided by a tapped coil which serves as an AC voltage divider for the output voltage and feedback signal.

Hartley Circuit

In this type of circuit, similar results are obtained with a capacitive voltage divider.

Colpitts Circuit

In this type of circuit, a piezoelectric crystal is used as a resonant circuit. Crystal Oscillators

The __________ means the crystal can vibrate mechanically when excited electrically and produce AC voltage output.

Piezoelectric effect

Typical values of resonant frequency of crystal oscillators. 0.5 to 30 MHz

The advantage of crystal over the LC circuit is _________. Very high Q which

results in good frequency stability

This type of circuit is used for audio oscillators. RC feedback

Oscillators

Typical frequencies for the RC feedback oscillators. 20Hz to 200kHz

MULTIVIBRATORS

The ________ is in a class by itself as an oscillator because it is important as a pulse generator in digital electronics.

Multivibrator (MV)

Multivibrator serves as a __________ to synchronize the timing in a digital system for the switching of pulses.

Reference clock

The voltage levels oscillate between the high and low levels because of the changes between conduction and cutoff in the MV circuit is sometimes called _________ because of the periods of cutoff.

Relaxation Oscillator

True or false: the Multivibrator operates as an oscillator without need for any input signal.

True

The Multivibrator is a ___________. Pulse Generator

In Multivibrator, _______ in a stage means it is turned on with driving voltage at the input.

Conduction

In Multivibrator, the OFF means that the stage in not conducting because of _________ at the input.

Cutoff Voltage

In Multivibrator, the ON means that the stage is conducting and the output voltage is _______.

Low

The __________ is a type of Multivibrator which is not stable in terms of the ON and OFF states of their stage. This circuit is a free-running oscillator.

Astable Multivibrator

The __________ is a type of Multivibrator that can be made to remain stable with either stage OFF and the other ON. It has two stable states.

Bistable Multivibrator

The function of forcing the stage into conduction when the circuit stays in one of these states until an input pulse is applied to the off stage to make it

Triggering


42

conduct.

The name _________ is used for the bistable Multivibrator circuit to describe this idea of switching the ON-OFF states one way and then the opposite way by means of input trigger pulses.

Flip-flop

This circuit has only one stable state. An input pulse is needed to trigger the OFF stage in to conduction.

Monostable or One-shot

Multivibrator

MODULATION

It can be defined as modifying the characteristics of one waveform with the variations in another signal.

Modulation

Common examples of modulation. AM and FM

The frequencies of carrier wave must be much ______ than the modulating frequency.

Higher

In AM radio broadcasting, audio frequency signals modulate a __________. RF carrier wave

The lower-frequency signal for the modulation. Baseband signal

In AM and FM radio broadcasting, the baseband modulation is a ____________.

Audio signal

In television, ________ is used as the baseband modulation. Video signal

Three characteristic of the carrier wave in baseband modulation.

Peak-to-peak

amplitude,

instantaneous

frequency, and phase

angle

The carrier input to the modulator comes from an RF oscillator. Amplitude Modulation

____________ means that the output amplitudes are not exactly proportional to the input signal.

Nonlinear

Amplification

In the AM output signal, the _________ have variations that correspond to the audio modulation.

RF peak-to-peak

amplitude

The outline of varying amplitudes. Modulation envelope

True or false: the RF amplitude variations are symmetrical around the zero axis.

True

Frequency spacing of AM radio broadcasting. 10kHz

Frequency spacing is needed in AM radio broadcast for the bandwidth of __________ with an AF baseband signal.

±5kHz

AF baseband signal of AM radio broadcast. 50 to 5000 Hz

In television service, _________ channels are used for broadcasting. 6MHz

Frequency bandwidth of channel 2. 54-60MHz

Frequency bandwidth in television service is needed for a video baseband signal of _______.

0 to 4 MHz

A modulated signal needs more bandwidth than the carrier wave itself because ___________.

To allow for the

variations produced by

the modulation

The necessary bandwidth is at least ________ to the frequencies in the baseband signal.

Equal

More than 100% modulation cannot be used in an AM signal because ______________________.

The part of the

baseband signal would

be missing and the carrier amplitude is


43

zero.

In this method, the instantaneous frequency of the carrier wave is made to vary in step with the variation of voltage in the baseband signal.

Frequency Modulation

The FM radio broadcast band. 88-108 MHz

Frequency spacing of FM radio broadcast band. 200kHz or 0.2MHz

In this method, the instantaneous phase angle of the RF carrier wave is made to vary in step with the modulating voltage.

Phase Modulation

Phase modulation produces ____________. Equivalent FM or

Indirect FM

Phase angle produces a larger change in the ___________ for higher audio modulating frequencies.

RF carrier frequency

Many FM transmitters use a phase-modulator circuit because __________________.

Good frequency

stability.

This method is necessary with the pulses representing digital information. Pulse Modulation

Typical systems of pulse modulation. PAM, PFM, PWM, PCM

Pulse modulation is efficient because ______________. The carrier power is on

for only the time of the

pulses.

Pulse modulation needs ___________ for the harmonic frequency components of sharp pulses.

Greater bandwidth

DIODE RECTIFIERS

The non-conducting diode is practically an_________ circuit. Open

The current in the positive half-cycle of the diode is a __________ because it only flows in one direction.

Conventional current

or electron flow

A _________ can operate in such a way that it really serves as electronic switch.

Diode

Current can flow in the diode only when the ____ is posit ive. Anode

The diode is off when ___________. The anode is negative

A process of switching in accordance with a specific polarity. Commutating

One of the most common applications of the diode rectifier is the ___________.

DC power supply

Half-wave rectifier uses ________ diode because only one-half of the AC input cycles are used from DC output.

One

In the diode circuit, a __________ is used to act as a surge-limiter which prevents excessive current through the diode

Resistor

The capacitors in the half-wave rectifier circuit are used for ___________. Filters

The ___________ represents the combined resistance of all the load currents connected to the output of the DC power supply.

Output resistor

The DC output voltage may be higher than the RMS value of the AC input voltage because ______________.

The input filter capacitor can charge to

the peak value

The value of DC output voltage, compared to the AC input voltage, depends on ___________.

The amount of DC load

current

The circuit which have an opposite polarity of DC output. Inverted power supply

The frequencies of AC ripple. 60 to 120 Hz

The inductor filter of a power supply is an iron-core choke used as a Series components


44

_________.

The inductor filter of a power supply must have _______ reactance at the frequency of the AC ripple.

High

Half-wave rectifier with ___ diode is the basic power supply. One

A two diode power supply can be arranged in a _________ circuit. Full-wave rectifier

The higher ripple frequency means ________________. Easier to filter

A __________ is a rectifier circuit for small values of signal voltage. Detector

Type of diode that have less resistance. Germanium Diode

TROUBLESHOOTING THE DC SUPPLY VO LTAGE

The effect when the filters in a power supply do not have enough capacitance and the result is too much of the AC ripple component in the DC output voltage.

Hum

Troubles in a power supply are generally __________. No DC output and Insufficient DC output

CHAPTER 30: TRANSISTOR AMPLIFIERS

INTRODUCTION

Any _______ operates by having a small input able to control more power in the output circuit.

Amplifier

Amplifier circuits for __________ operate with a combination of AC and DC values.

AC signals

CIRCUIT CONFIGURATIONS

This description specifies which electrodes in the amplifier are used for input and output signals.

Circuit Configuration

The ___________ usually is the one that does not have any signal in the circuit configuration.

Common Electrode

True or false: all the circuit configurations of the transistor have reverse voltage for the collector and forward bias for the emitter-base junction.

True

The _________________ circuit is the one generally used for amplifiers because it has the best combination of current gain and voltage gain.

Common-Emitter

The only advantage of __________ is that it has the best stability with an increase in temperature.

Common-Base

The common-base circuit has no current gain from the input to output because ______________.

Collector current must

be less than emitter

current.

A transistor circuit which input voltage is applied to the base with respect to the grounded emitter.

Common-Emitter

The common-emitter has current gain because _____________. Collector current is

much larger than base

current.

The disadvantage of common-emitter circuit is that _______________ is amplified in the circuit.

Reverse leakage current

The only amplifier that inverts the polarity of signal voltage. Common-emitter


45

amplifier

A circuit configuration of the transistor which input voltage is applied to the base with respect to the grounded collector.

Common-collector

There is no voltage gain in common-collector circuit because __________.

The output signal

provides negative

feedback to the base

input.

The name __________ is generally used for the common-collector circuit. Emitter-follower

The emitter-follower circuit is often used for ____________. Impedance matching

The circuit configuration consists of two emitter followers connected in cascade.

Darlington Pair

CLASS A, B, OR C OPERATION

The amplifier class of operation is defined by the ________ that is able to produce output signal.

Percentage of the input signal

The class of operation depends on this two amplitudes:

DC bias compared to cutoff value and the

peak AC signal

compare with DC bias.

The class of operation determines the ____________ of the signal may be produced by the amplifier.

Power efficiency and

distortion

In this type of operation, the DC bias allows an average output current of about one-half the maximum value.

Class A

True of false: output current of class A operation can cut-off. False, It never cut-off

In this type of operation, the output current flows 180°, or approximately one-half of the input cycle.

Class B

In class B operation, the negative half-cycles of input signal are cut-off in the output because _____________.

Output current then is

zero.

True or false: class b operation requires more DC bias and more AC signal drive than the class A.

True

Class B operation with a single stage corresponds to ___________ of the AC signal input.

Half-wave rectification

In this type of operation, the output current flows for less than one-half the input cycle. Typical operation is 120° of output current during the positive half-cycle of input.

Class C

Class C operation is used for ______________ because of its high efficiency.

Tuned RF power

amplifiers

In class A operation, distortion is ______, but also are AC power output and efficiency.

Lowest

Typical values of percent distortion of class A operation. 5 to 10

Typical values of efficiency of class A operation. 20 to 40%

Typical values of efficiency of class C operation. 80%

The ___________ operation allows the greatest AC power output but with the most distortion.

Class C

With audio amplifiers, _________ must be used in a single stage for minimum distortion.

Class A

A _______________ amplifying an amplitude-modulated signal must operate class A for minimum distortion of the modulation.

RF stage


46

Most small-signal amplifiers operate in ______________. Class A

The circuit used in class B which in each stage of which supplies opposites half-cycles of the signal input.

Push-pull amplifier

Push-pull circuit is often used for _______________. Audio power output to

a loudspeaker.

In class C operation, __________ circuit can provide a full-sine wave cycle of output for each pulse of the output current.

LC circuit

Class C operation have high efficiency because ___________. Output current is very

low compared with the

peak signal amplitude.

A ___________ operates as a class C operation. Pulse clipper circuit

ANALYSIS OF COMMON-EMITTER (CE) AMPLIFIER

Typical values of VBE are in _________ for junction transistor. Tenths of a volt

The required bias at the base for a class A amplifier is _________ for silicon.

0.6 to 0.7 V

The required bias at the base for a class A amplifier is _________ for germanium.

0.2 to 0.3 V

A __________ means that the amplifier conducts current of 360° of the signal cycle for minimum distortion.

Class A operation

The maximum AC input signal without overload distortion. ±0.1 V

Without any forward bias, a junction transistor is cut off by __________. Barrier potential

The __________ is the lowest VBE that allows appreciable collector current. Cut-in voltage

The __________ is the highest VBE that allows it to produce proportional changes in collector current.

Saturation voltage

True or false: at saturation, the maximum collector current does increase with an increase of forward voltage.

False, it doesn’t

increase

The transistor amplifier itself is usually labeled ________. Q

True or false: one supply voltage is used for both collector and base in the common-emitter circuit.

True

The signal changes in _________ produce variations in the voltage drop across the collector load for the output circuit.

Collector current (iC)

In signal analysis of the common-emitter circuit, positive signal voltage in the forward direction __________ the base current.

Increase

True or false: the base bias produces the required collector current with the specified RL.

True

Each of the cascaded amplifiers increases the __________ enough to drive the next stage.

Signal current

COLLECTOR CHARACTERISTIC CURVES

The _________ shows the volt-ampere characteristics for the collector and also provided by the manufacturer in a transistor manual or application notes.

Characteristic curve

For the common-emitter circuit, the collector curves are for different values of __________.

Base current

For common-base circuit, the collector curves are for different values of __________.

Emitter current


47

For more collector current, the transistor needs more ________. Base current

This specification for a junction transistor indicates the amount of current gain in the common-emitter circuit.

Beta (β) characteristic

True or false: there is a unit for beta (β). False, because it is a

ratio of two currents.

This ratio compares collector current to emitter current. Alpha (α) characteristic

LETTER SYMBOLS FOR TRANSISTORS

Symbols in capital letters and subscripts are used for _________. Average DC values

Double subscripts that are repeated in VCC indicate __________. The supply voltage that

does not change.

The symbol _________ is used to denote the DC supply voltage for the emitter.

VEE

The small letters are used for ___________.

Instantaneous value

that vary with

fluctuating DC waveform

A small letter in the subscript indicates the _____________. AC waveform

A capital letter with a small in the subscript indicates the _____________ RMS value of the AC

component

The symbol ____________ denotes reverse leakage current. ICBO

Small letter “h” stands for ___________. Hybrid parameters

FET AMPLIFIERS

This circuit corresponds to the common-emitter with junction transistors. With an FET, the input signal is applied to the gate which is the control electrode. Amplified output signal is taken from the drain. The source is the common electrode

Common-source circuit

In this circuit, the input signal is applied to the source, with output from the drain.

Common-gate circuit

In this circuit, the input signal is applied to the gate, with output from the source.

Common-drain circuit

Common-drain circuit is named ________, corresponding to the emitter follower with junction transistors.

Source follower

The circuit configuration used most often for FET amplifiers. Common-source

This factor is important for the FET because it specifies how the gate voltage controls the drain current.

Transconductance (gm)

The unit of gm because it is a ratio of current over voltage. Siemens

The ______ indicates a mutual conductance relation of how the effect of the input voltage at the gate is transferred to the output current in the drain current.

gm

TYPES OF DISTORTIONS

The __________ has been introduced in the amplifier when the waveform of the amplified output signal is not exactly the same as that of the input signal.

Distortion

The _________ is produced by operating the amplifier over the nonlinear Amplitude distortion


48

part of the transfer characteristic of the amplifier.

This distortions occurs when the input signal or drive is excessive Overload distortion

Any _________ in a class A amplifier is a measure of the amount of amplitude distortion.

Shift of DC level

The change of the relative amplitudes is the same as introducing harmonic components not present in the input signal.

Harmonic distortion

A ___________ is composed of a fundamental sine wave at the same frequency plus odd-harmonic frequency components.

Square Wave

Typical values of harmonic distortion at full power output. 1to 5%

The effect which results in harmonics introduced in the amplifier can combine with each other or with original frequencies to produce new frequencies that are not harmonics of the fundamental.

Intermodulation

distortion

____________ is the reason for the rough, unpleasant sound of amplitude distortion, because that distortion is not harmonically related to the signal.

Intermodulation

The distortion that results when the gain of the amplifier varies with frequency.

Frequency distortion

The uniform gain at the center of the curve. Flat response

NEGATIVE FEEDBACK

___________ means coupling part of the amplified output signal back to the input.

Feedback

The result when the feedback is in phase with the input signal. Positive feedback

Positive feedback is used in _________. Oscillator circuits.

The result when the feedback is out-of- phase with the input signal. Negative feedback

The amount of feedback is determined by __________ which is also can vary the feedback for different frequencies.

Feedback network

The amount of amplifier gain with feedback. Closed-loop gain

The amount of amplifier gain without feedback. Open-loop gain

The reason why negative feedback reduces distortion is because ___________.

There is partial

cancellation of the out-

of-phase signals

CHAPTER 31: DIGITAL ELECTRONICS

INTRODUCTION

It involves circuits that operate using only two voltage levels for all input and output signals.

Digital Electronics

The two voltage levels most commonly used in digital electronics. 0 and 5 v

Modern calculators and computers that process binary numbers use decision-making elements called _______.

Logic Gates

Two broad categories of digital logic circuits. Combinational logic

circuits and sequential

logic circuits

A circuit is considered a ___________ if its output goes either low or high with a specified combination input signals.

Combinational logic

circuits

This circuit must have a definite order or sequence for its inputs before the Sequential logic circuits


49

desired output is obta ined.

The basic building block of combinational logic circuits. Logic gates

The basic building block of sequential logic circuits. Flip-flop

COMPARING BINARY AND DECIMAL NUMBERS

All number systems have a _________ which specifies how many digits can be used in each place count.

Base or radix

In the decimal number system, the base is _____. 10

In the binary number system, the base is ____. 2

The most commonly used number system. Decimal

A number system that is used in digital electronics. Binary

True or false: typical binary numbers are often written in groups of four or eight digits.

True

Each digit of binary numbers is referred to as a _______. Bit

A string of four bits are called _________. Nibble

Eight bits makes a __________. Byte

For either binary or decimal numbers, the digit at the right is referred to as a _________.

Least significant digit (LSD)

The digit at the left-most is referred to as a _________. Most significant digit

(MSD)

DECIMAL TO BINARY CONVERSION

The method used to convert a decimal number to its binary equivalent. It requires successive divisions by 2.

Double-dabble

HEXADECIMAL NUMBERS

It is used extensively in the microcomputer field. It has a base of 16. Hexadecimal Numbers

The first ten digits in the hexadecimal system are represented by _________.

0-9

The ______________ are used to represent the numbers 10, 11,12,13,14 and 15.

A-F

The method used to convert a decimal number to a hexadecimal number. Hex-dabble

The process of replacing long strings of data with a much shorter string. Chunking

BINARY CODED DECIMAL SYSTEM

Commonly used number system in the field of digital electronics in which expresses each decimal digit as a 4-bit nibble.

Binary coded decimal

system (BCD)

The highest BCD value that a 4-bit nibble could represent. 9

It is used when it is necessary to transfer decimal information into or out of a digital machine.

BCD number system

THE ASCII CODE

The _____________ is an alphanumeric code; it has binary values for each letter, number, and symbol.

ASCII Code


50

Each keystroke on an ASCII keyboard produces a corresponding _________ for the designated character.

Binary code

ASCII code represented by a ___________ in the form of X6, X5, X4, X3, X2, X1, and X0.

7-bit binary word

The first bit of ASCII code. X6

The ASCII code for the capital letter “W”. 1010111

LOGIC GATES , SYMBOLS , AND TRUTH TABLES

It is a circuit that has one or more input signals but only one output signal. Logic Gate

The ______________ list all input possibilities and the corresponding output for each input.

Truth table

It has only one input and one output, where the output is the opposite of the input.

Inverters

The small bubble on inverter diagram represents __________. Inversion

The number of possibilities listed in the truth table is __________. 2N

A logic circuit with two or more inputs but only one output. The output is high if any or all inputs are high. The output is low only when all inputs are low.

OR Gate

A logic circuit with two or more inputs. The output is low if any or all inputs are low. The output is high only when all inputs are high.

AND Gate

A logic circuit with two or more inputs but only one output. The output is low if any or all inputs are high. The output is low only when all inputs are low.

NOR Gate

A logic circuit with two or more inputs but only one output. The output is high if any or all inputs are low. The output is low only when all inputs are high.

NAND Gate

A logic circuit with two or more inputs but only one output. The output is high when an odd number of 1s is applied to its inputs. The output is low when an even number of 1s is applied to its inputs.

XOR Gate

A logic circuit with two or more inputs but only one output. The output is high when an even number of 1s is applied to its inputs. The output is low when an odd number of 1s is applied to its inputs.

XNOR Gate

BOOLEAN ALGEBRA

Logical system of using binary information in digital circuits. Boolean algebra

For the basic logic inverter the Boolean algebra expression would be ____________.

X = Ā

The over-bar above the input variable A represents __________. Inversion or

complementing

To invert or complement, a binary number means to change it to the _____. Opposite state

The “+” sign stands for ___________. OR addition

The multiplication dot stands for __________. AND operation

The Boolean expression for the NOR gate. X=B+A

The Boolean expression for the NAND gate. X=B•A

The Boolean expression for the XNOR gate. X=BA⊕ The Boolean expression for the XOR gate. X=BA⊕


51

DEMORGAN’S THEOREM

Important principles of Boolean algebra which can help to greatly simplify expressions in which a product or sum is inverted.

Demorgan’s Theorem

First theorem of Demorgan’s theorem. B . A=B+A

Second theorem of Demorgan’s theorem. B + A=B•A

ACTIVE HIGH/ACTIVE LOW TERMINOLOGY

When an input or output line on a logic gate symbol does not show a bubble, it indicates that these lines are _________.

Active high

When an input or output line on a logic gate symbol does show a bubble, these lines are said to be _________.

Active low

The presence or absence of _________ on the inputs and output of logic gates indicates whether a line is considered to be high or low.

Bubble

When an input variable or output in a Boolean expression has no over-bar, it means that the input variables or outputs are ______.

Active high

If an input variable or output in a Boolean expression does have an over-bar, it means that the input variables or outputs are ______.

Active low

TREATING UNUSED INPUTS ON LOGIC GATES

Unused inputs on AND and NAND gates should be connected directly to __________ or tied to another input that is being used.

VCC (+5V)

Unused inputs are always ________. High

The unused input should never be tied to ground for an AND gate because ______________.

The output would

always be low.

Unused inputs on OR and NOR gates should be tied to ________. Ground

The unused inputs on OR gates should never be tied to VCC because ___________.

The output will remain

high.

NAND OR NOR gates can be used as __________ if all inputs are tied together.

Inverters

TTL CIRCUITS AND THEIR CHARACTERISTICS

It is the most popular family of digital devices. Transistor-transistor Logic (TTL)

It is a group of compatible devices with the same logic voltage levels and DC supply voltage.

Digital family

The __________ are categorized according to the number of logic gates contained in one IC.

Digital IC

Two basic technologies for manufacturing digital ICs. Bipolar and MOS

technology

It fabricates bipolar transistors on an IC. Bipolar technology

It fabricates MOSFETS on an IC. MOS technology

It is used for SSI and MSI. Bipolar technology

It is used for LSI, VLSI, and USLI. MOS technology

True or false: bipolar device have faster switching speeds than MOS devices.

True


52

It is used when it is required to package hundreds or thousands of logic gates into one chip.

MOS technology

The TTL devices are often referred to as the ___________. 7400 series

The 7400 device is a __________, which means that this chip contains four 2-input NAND gates inside.

Quad 2-input NAND gate

The 7404 device is called ________. Hex inverter

The 7427 contains ___________. Three, 3-input NOR

gates

The 7400 series uses VCC of _____________. +5V

The arrangement of schematic diagram of hex inverter in which used because of its low output impedance.

Totem-pole output

If an input to a standard TTL logic gate is 0.8V or less, the logic gate recognizes this as ______.

Low input

If an input to a standard TTL logic gate is 2.0V or more, the logic gate recognizes this as ______.

High input

The range of two input voltage levels of TTL logic gates are referred to as a ___________.

Worst case input

voltages

The maximum number of TTL inputs that can be reliably driven by a standard TTL output is called the _________.

Fan-out

7400 series device will work over a temperature of ___________. 0° to 70° C

Range of supply voltage of 5400 series device. 4.5 - 5.5 V

Temperature range of 5400 series device. -55° to 125°C

CMOS DEVICES

The basic logic gates such as inverter, AND, OR, NAND, and NOR gates are manufactured using ____________.

MOSFET

Disadvantages of MOS. Slower switching speed

and extreme sensitivity

to ESD

Complementary metal oxide semiconductor field effect transistor CMOS

True or false: CMOS devices have slower switching speeds as compared to TTL.

True

The MOSFETS most often used in the construction of logic gates. P-channel and N-

channel enhancement

types

Commonly used CMOS device series. 4000 series

Range of supply voltage of 4000 series. 3-15 V

COMBINATIONAL LOGIC CIRCUITS

Digital circuits often consist of several different ________, interconnected in such a way as to perform a specific logic function.

Logic gate

Sum of products is called ________. Minterm Boolean

expression

Any logic circuit of AND gates and OR gates can be replaced with equivalent _________.

NAND gates


53

BINARY ADDERS

The _____________ of computer is where arithmetic operations such as addition take place.

Arithmetic Logic Unit

(ALU)

Logic circuits that has provisions for carry-out of 1 but not carry-in. Half adder

Digital circuit that has provisions for carry-in of 1 and carry-out of 1. Full adder

FLIP-FLOPS

It is a digital circuit that has two stable states. It can hold or store digital data.

Flip-flop

True or false: the flip-flop can remain in either stable state indefinitely. True

Flip-flops are used to store ____________. Binary information

The __________________ that can store bits of data are an essential part of any computer system.

Digital memory circuits

The most basic type of flip-flop that can be built using either two NOR gates or two NAND gates.

RS flip-flop

The flip-flop is said to be set when __________. Q=1 and Q’=0

The flip-flop is said to be reset when __________. Q=0 and Q’=1

These can pull TTL inputs to ground for binary 0. Pull-down resistors

The maximum resistance of pull-down resistors should not exceed ______. 500Ω

These pulls the TTL inputs up to +VCC for a binary 1. Pull-up resistors

It is a RS flip-flop that has a clock (CLK) input. Clocked RS flip-flop

It is a square wave that has a maximum value of +5V and minimum value of 0V.

Clock voltage

It prevents the flip-flop outputs from changing until exactly right time. Clock input signal

Type of flip-flop in which the flip-flop can edge-triggered. D-type flip-flop

The flip-flop is edge-triggered because the flip-flop only responds when the _____ is changing states.

Clock

This flip-flop will respond only to a negative-going clock pulse. JK flip-flop

In JK flip-flop, the flip-flop is ______ when the clock is low, high, or on its positive- going edge.

Inactive

BINARY COUNTERS AND REGISTERS

JK flip-flops can also be connected together to form a ________. Binary counter

These are used when it is necessary to count the number of clock pulses that arrive at a clock input.

Binary counters

Equivalent circuit of binary counters. Four JK flip-flop

The counter in which the output of one flip-flop is fed to the clock input of another.

Ripple counter

The _________ of the counter is the number of output states it has. Modulus

It is a digital circuit that can hold or store digital data. Buffer register

Equivalent circuit of buffer register. Memory circuit

NEW LOGIC SYMBOLS

In 1984, a new set of standard symbols was introduced by the _______________.

IIEE and ANSI


54

The _______ inside the inverter gate rectangle denotes a gate with only one input.

1

The _______ symbol inside the AND gate rectangle means the output will go active high only when the all inputs are active high.

&

The symbol inside the OR gate rectangle means that the output will go active high when one or more inputs are active high.

≥

TROUBLESHOOTING DIGITAL CIRCUITS

One of the most commonly used pieces of test equipment for troubleshooting digital circuits. It has two LED indicators that light to indicate whether a voltage level is equivalent to binary 0 or binary 1.

Logic probe

It is a troubleshooting tool that generates a short-duration pulse when activated manually, usually by pressing a button.

Logic pulsers

A very special oscilloscope that has either 8 or 16 input leads for connection to the circuit, which allows the electronic technician or engineer to see how all the different circuits are functioning at the same time.

Logic analyzer

A very useful tool to help determine the exact location of a short without breaking the circuit.

Current tracer

CHAPTER 32: INTEGRATED CIRCUITS

INTRODUCTION

This is actually microelectronic circuits. Integrated Circuits

It is used in computers, calculators, and digital clocks as well as many other digital devices.

Digital IC

It is used in analog-type circuits such as audio amplifiers, voltage regulators, operational amplifiers, and radio frequency circuits.

Linear IC

True or false: most linear IC’s are high-power devices. False, there are low-power devices.

OPERATIONAL AMPLIFIERS AND THEIR CHARACTERISTICS

It is a high-gain, direct-coupled, differential amplifier. Operational Amplifier

(Op amp)

Common op amp which different manufacturers produce. 741

The output of op amp is taken at the emitters of transistors which are connected in a _____________ configuration.

Push-pull

The push-pull configuration in the output of op amp allows the op amp to have a ____________.

Very low output

impedance

The ___________ affects the operation of the op amp at higher frequencies and it is used to prevent undesirable oscillations from occurring within the op amp.

Compensating

capacitor

Typical value of compensating capacitor of the op amp. 30pF

Figure of schematic symbol of an op amp. Triangle

Pin 7 of 741 op amp connects to ________. +VCC

Pin __ of 741 op amp connects to -VCC. Pin 4

Pin _____ of 741 op amp connects to the op amp input. Pin 2 and 3


55

Pin 6 of 741 op amp connects to the ________. Op amp output

The _____________ of an op amp is its voltage gain when there is no negative feedback.

Open-loop voltage gain

AVOL

The open-loop voltage gain of an op amp is the ratio of _________. Output voltage to its

differential input

voltage

The typical value of AVOL for a 741 op amp. 200,000

When the voltage at the non-inverting (+) input is made negative with respect to its inverting (-) input, the output is _________.

Negative

The upper limit of output voltage of op amp. Positive saturation

voltage

The lower limit of output voltage of op amp. Negative saturation

voltage

If the output voltage of any op amp lies between positive and negative saturation voltage, then the differential input voltage can be considered as ________.

Zero

Typical input bias current of 741 op amp. 80nA

The difference between the current flowing for the non-inverting terminal and the current flowing from the inverting input terminal.

Input offset current

Typical input offset current of 741 op amp. 20nA

The frequency where gain of open-loop equals to 1. Unity frequency

Unity frequency of 741 is approximately ________. 1MHz

The ___________ tells how fast the output voltage can change. Slew rate

The slew rate of an op amp is specified in _____. Volts per microsecond

Slew rate of 741 op amp. 0.5V/µs

Slew rate distortion of a sine wave produces a _________. Triangular wave

If the initial slope of the output waveform exceeds the slew rate of the op amp, ____________ will occur.

Slew rate distortion

The _________ of an op amp circuit is the highest undistorted frequency out of an op amp for a given slew rate and peak voltage.

Power bandwidth

The output short circuit current of 741 op amp. 25mA

It is defined as its ability to amplify differential input signals while attenuating or rejecting common mode signals.

Common mode

rejection ratio (CMRR)

Typical CMRR of 741 op amp. 90dB

OP AMP CIRCUITS

Most op amp uses ____________ feedback. Negative

It reduces the overall voltage gain of the op amp circuit. Negative feedback

Type of amplifier in which the input and output signals are 180° out of phase when input voltage is applied to the inverting (-) input terminal.

Inverting amplifier

It provides the negative feedback of inverting amplifier, which in turn controls the circuit’s overall voltage gain.

Resistors RF and Ri

Type of op amp circuit in which the input signal drives the non-inverting input terminal of the op amp.

Non-inverting amplifier

For the non-inverting amplifier circuit, the input and output signals are always ___________.

In phase

The op amp circuit connected to provide a voltage gain of one, or unity. Voltage follower

Voltage follower provides no voltage gain because op amp circuits will Buffer


56

______ the voltage source for the load.

THREE- TERMINAL IC VOLTAGE REGULATORS

IC’s feature when the internal temperature of the chip reaches a certain temperature, the regulator shuts down and prevents the chip from getting any hotter.

Thermal shutdown

The range of load current of IC voltage regulators. 100mA – 3A

The popular series of three-terminal IC voltage regulators. LM340 series

To ensure proper operation of a three-terminal IC voltage regulator, the unregulated DC input voltage must always be at least ________ higher than its regulated DC output voltage.

2-3V

This IC has 1.25V reference voltage between its output terminal and adjustment terminal.

LM317

555 TIMERS

A very popular IC used in timing circuits. 555 timers

Range of supply voltage of 555 timers. 5-18V

This circuit will produce a single output pulse when a trigger input pulse is applied.

Monostable (one shot)

multivibrator

True or false: in monostable operation, the larger the RC time constant, the greater the length of the output pulse.

True

In this circuit, the capacitor voltage is initially 0V when power is applied. Astable multivibrator

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