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Illustrative Material Long Report

The Transistor: Birth of the Age of Electronics

A Technical Report Submitted to College of Asian Institute of Computer Studies

In Partial Fulfillment of the Subject Requirements in English 4

(Technical Writing)

By:

Francis PrincesaRenalyn BrusolaJeffrey Ramos

Kenneth Lagrimas

TABLE OF CONTENTS

CHAPTER I

INTRODUCTION…………………………………………….1

CHAPTER II

STATEMENT OF THE PROBLEM…………………………………………………...3

OBJECTIVE OF THE STUDY…………………………………………………..…...4

IMPORTANCE OF THE STUDY……………………………………………………….4

CHAPTER III

DEFINITION OF TERMS………….…………………………………………...5

CHAPTER IV

REVIEW OF RELATED LITERATURE…………………….…………………………8

CHAPTER V

ILLUSTRATION OF TRANSISTOR……………………………………………...11

CHAPTER VI

OTHER RESOURCES………….…………………….…………….16

CHAPTER VII……………………………………………………………………...17

I.INTRODUCTION

A transistor is a semiconductor device used to amplify or switch electronic signals. It is made of a solid piece of semiconductor material, with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current flowing through another pair of terminals. Because the controlled (output) power can be much more than the controlling (input) power, the transistor provides amplification of a signal. Some transistors are packaged individually but many more are found embedded in circuits. The transistor is the fundamental building block of modern electronic devices, and its presence is ubiquitous in modern electronic systems

A transistor is a semiconductor device that uses a small amount of voltage or electrical current to control a larger change in voltage or current. Because of its fast response and accuracy, it may be used in a wide variety of applications, including amplification, switching, voltage stabilization, signal modulation, and as an oscillator. The transistor is the fundamental building block of both digital and analog circuits the circuitry that governs the operation of computers, cellular phones, and all other modern electronics. Transistors may be packaged individually or as part of an integrated circuit chip, which may hold thousands of transistors in a very small area.

The term "transistor" originally referred to the point contact type, which saw very limited commercial application, being replaced by the much more practical bipolar junction types in the early 1950s. Today's most widely used schematic symbol, like the term "transistor", originally referred to these long-obsolete devices. For a short time in the early 1960s, some manufacturers and publishers of electronics magazines started to replace these with symbols that more accurately depicted the different construction of the bipolar transistor, but this idea was soon abandoned.

In analog circuits, transistors are used in amplifiers, (direct current amplifiers, audio amplifiers, radio frequency amplifiers), and linear regulated power supplies. Transistors are also used in digital circuits where they function as electronic switches, but rarely as discrete devices, almost always being incorporated in monolithic Integrated Circuits. Digital circuits include logic gates, random access memory (RAM), microprocessors, and digital signal processors (DSPs)

An electrical signal can be amplified by using a device that allows a small current or voltage to control the flow of a much larger current. Transistors are the basic devices providing control of this kind. Modern transistors are divided into two main categories: bipolar junction transistors (BJTs) and field effect transistors (FETs). Application of current in BJTs and voltage in FETs between the input and common terminals increases the conductivity between the common and output terminals, thereby controlling current flow between them. The transistor characteristics depend on their type.

Modern transistors are divided into two main categories: bipolar junction transistors (BJTs) and field effect transistors (FETs). Application of current in BJTs and voltage in FETs between the input and common terminals increases the conductivity between the common and output terminals, thereby controlling current flow between them.

The first silicon transistor was produced by Texas Instruments in 1954. This was the work of Gordon Teal, an expert in growing crystals of high purity, who had previously worked at Bell Labs. The first MOS transistor actually built was by Kahng and Atalla at Bell Labs in 1960.

Physicist Julius Edgar Lilienfeld filed the first patent for a transistor in Canada in 1925, describing a device similar to a Field Effect Transistor or "FET". However, Lilienfeld did not publish any research articles about his devices, and in 1934, German inventor Oskar Heil patented a similar device In 1947, John Bardeen and Walter Brattain at AT & T 's Bell Labs in the United States observed that when electrical contacts were applied to a crystal of germanium, the output power was larger than the input. Solid State Physics Group leader William Shockley saw the potential in this, and over the next few months worked to greatly expand the knowledge of semiconductors, and thus could be described as the "father of the transistor". The term was coined by John R. Pierce. According to physicist/historian Robert Arns , legal papers from the Bell Labs patent show that William Shockley and Gerald Pearson had built operational versions from Lilienfeld's patents, yet they never referenced this work in any of their later research papers or historical articles.

2.1 STATEMENT OF THE PROBLEM

How the transistors work?

The design of a transistor allows it to function as an amplifier or a switch. This is accomplished by using a small amount of electricity to control a gate on a much larger supply of electricity, much like turning a valve to control a supply of water.

Where the transistor use?

A transistor is a semiconductor device used to amplify or switch electronic signals. It is made of a solid piece of semiconductor material, with at least three terminals for connection to an external circuit.

The bipolar junction transistor, or BJT, was the most commonly used transistor in the 1960s and 70s. Even after MOSFETs became widely available, the BJT remained the transistor of choice for many analog circuits such as simple amplifiers because of their greater linearity and ease of manufacture. Desirable properties of MOSFETs, such as their utility in low-power devices, usually in the CMOS configuration, allowed them to capture nearly all market share for digital circuits; more recently MOSFETs have captured most analog and power applications as well, including modern clocked analog circuits, voltage regulators, amplifiers, power transmitters, motor drivers, etc.

What is the simplified operation of the transistor?

The essential usefulness of a transistor comes from its ability to use a small signal applied between one pair of its terminals to control a much larger signal at another pair of terminals. This property is called gain. A transistor can control its output in proportion to the input signal, that is, can act as an amplifier. Or, the transistor can be used to turn current on or off in a circuit as an electrically controlled switch, where the amount of current is determined by other circuit elements.

The two types of transistors have slight differences in how they are used in a circuit. A bipolar transistor has terminals labeled base, collector, and emitter. A small current at the base terminal (that is, flowing from the base to the emitter) can control or switch a much larger current between the collector and emitter terminals. For a field-effect transistor, the terminals are labeled gate, source, and drain, and a voltage at the gate can control a current between source and drain. Charge will flow between emitter and collector terminals depending on the current in the base. Since internally the base and emitter connections behave like a semiconductor diode, a voltage drop develops between base and emitter while the base current exists. The amount of this voltage depends on the material the transistor is made from, and is referred to as VBE.

III. DEFINITION OF TERM

Semiconductor Device- electronic components that exploit the electronic properties of semiconductor materials, principally silicon, germanium, and gallium arsenide. Semiconductor devices have replaced thermionic devices (vacuum tubes) in most applications.

Electronics- is that branch of science and technology which makes use of the controlled motion of electrons through different media and vacuum.

Semiconductor- is a material that has an electrical conductivity between that of a conductor and an insulator, that is, generally in the range 103

siemens per centimeter to 10−8 S/cm.

Power- is the rate at which work is performed or energy is converted.

Integrated Circuit- is a miniaturized electronic circuit (consisting mainly of semiconductor devices, as well as passive components) that has been manufactured in the surface of a thin substrate of semiconductor material.

Electronic Circuit- is composed of individual electronic components, such as resistors, transistors, capacitors, inductors, and diodes, connected by conductive wires or traces through which electrical current can flow.

Field Effect Transistor- relies on an electric field to control the shape and hence the conductivity of a channel of one type of charge carrier in a semiconductor material.

Germanium- is a chemical element with the symbol Ge and atomic number 32. It is a lustrous, hard, grayish-white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon.

Computer- s a programmable machine that receives input, stores and manipulates data, and provides output in a useful format.

Oscillator- is an electronic circuit that produces a repetitive electronic signal, often a sine wave or a square wave.

Bipolar Junction Transistor- is a three-terminal electronic device constructed of doped semiconductor material and may be used in amplifying or switching applications.

Conductivity- is a measure of a material's ability to conduct an electric current.

Point Contact Transistor- was the first type of solid-state electronic transistor ever constructed. It was made by researchers John Bardeen and Walter Houser Brattain at Bell Laboratories in December 1947.

Electronic Symbol- is a pictogram used to represent various electrical and electronic devices (such as wires, batteries, resistors, and transistors) in a drawing of an electrical or electronic circuit.

Analog Circuits- is one that uses continuous time voltages and currents. This is opposed to digital devices where devices states are presented by discrete time and discrete values (almost always binary, although three or four state non-volatile memory devices where proposed).

Power Supply- is a reference to a source of electrical power. A device or system that supplies electrical or other types of energy to an output load or group of loads is called a power supply unit or PSU. The term is most

commonly applied to electrical energy supplies, less often to mechanical ones, and rarely to others.

Discrete Devices- is an electronic component with just one circuit element, either passive (resistor, capacitor, inductor, diode) or active (transistor or vacuum tube), other than an integrated circuit.

Digital Circuits- are systems that represent signals as discrete levels, rather than as a continuous range.

Logic Gates- performs a logical operation on one or more logic inputs and produces a single logic output.

Random Access Memory- is a form of computer data storage. Today, it takes the form of integrated circuits that allow stored data to be accessed in any order

Microprocessors- incorporates most or all of the functions of a computer's central processing unit (CPU) on a single integrated circuit (IC, or microchip)

Digital Signal Processors- is a specialized microprocessor with an optimized architecture for the fast operational needs of digital signal processing.

Diodes- is a two-terminal electronic component that conducts electric current in only one direction. The term usually refers to a semiconductor diode, the most common type today, which is a crystal of semiconductor connected to two electrical terminals, a P-N junction.

Resistors- is a two-terminal electronic component that produces a voltage across its terminals that is proportional to the electric current passing through it in accordance with Ohm's law:

Capacitors- is a passive electronic component consisting of a pair of conductors separated by a dielectric (insulator).

Electromagnetic Field is a physical field produced by electrically charged objects.

V. ILLUSTRATION OF TRANSISTOR

Vacuum tubes were made containing several three terminal devices called triodes.

Radio brought information rapidly to the masses and was the first widely used electronic device in the home.

The largest computers based on vacuum tubes had racks and racks of tubes filling large rooms.

The first point contact transistor made use of the semiconductor germanium. Paper clips and razor blades were used to make the device.

Individual electronic components were soldered on to printed circuit boards.

Integrated circuits placed all components in one chip, drastically reducing the size of the circuit and its components.

VI. OTHER RESOURCES

Science and Technology Physics Updated Edition

http://en.wikipedia.org/wiki/Transistor

http://images.search.yahoo.com/search/images?fr=yfp-t-701- s & toggle=1 & cop=mss & ei=UTF8 & rd=r2 & p=transistor

http://en.wikipedia.org/wiki/Semiconductor

http://en.wikipedia.org/wiki/Electrical_Conductor

http://en.wikipedia.org/wiki/Electromagnetic_field

http://www.newworldencyclopedia.org/entry/Transistor

http://www.newworldencyclopedia.org/entry/Integrated_circuit

http://nobelprize.org/educational_games/physics/transistor/ history/

2.2 OBJECTIVE OF THE STUDY

To be able to know about the transistor

To be able to know the uses of transistor

To develop and enhance our knowledge and skill

To know the advantages and disadvantages of transistor

2.3 IMPORTANCE OF THE STUDY

The transistor is the key active component in practically all modern electronics, and is considered by many to be one of the greatest inventions of the twentieth century. Its importance in today's society rests on its ability to be mass produced using a highly automated process (semiconductor device fabrication) that achieves astonishingly low per-transistor costs.

Although several companies each produce over a billion individually-packaged (known as discrete) transistors every year, the vast majority of transistors now produced are in integrated circuits (often shortened to IC, microchips or simply chips), along with diodes, resistors, capacitors and other electronic components, to produce complete electronic circuits. A logic gate consists of up to about twenty transistors whereas an advanced microprocessor, as of 2006, can use as many as 1.7 billion transistors (MOSFETs). "About 60 million transistors were built this year [2002] ... for [each] man, woman, and child on Earth."

The transistor's low cost, flexibility, and reliability have made it a ubiquitous device. Transistorized mechatronic circuits have replaced electromechanical devices in controlling appliances and machinery. It is often easier and cheaper to use a standard microcontroller and write a computer program to carry out a control function than to design an equivalent mechanical control function.

Adapted from a technical report submitted to Mrs.

Rosita Ramos by the

Associate in Computer Science

Students in Asian Institute of Computer Studies.