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History of Electronics

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three key components the vacuum tube, the transistor, and the integrated circuit. ... By the mid-1950s, television had surpassed radio for home use and entertainment. ... – PowerPoint PPT presentation

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Title: History of Electronics


1
History of Electronics
  • The is a story of the twentieth century
  • three key componentsthe vacuum tube, the
    transistor, and the integrated circuit.
  • 1883, Thomas Alva Edison discovered that
    electrons will flow from one metal conductor to
    another through a vacuum. ( Edison effect)
  • In 1904, John Fleming applied the Edison effect
    in inventing a two-element electron tube called a
    diode,
  • Lee De Forest followed in 1906 with the
    three-element tube, the triode.

2
  • Guglielmo Marconi pioneered the development of
    the wireless telegraph in 1896 and long-distance
    radio communication in 1901. Vacuum tubes
    strengthened weak audio signals and allowed these
    signals to be superimposed on radio waves.
  • In 1918, Edwin Armstrong invented the
    "super-heterodyne receiver" that could select
    among radio signals or stations and could receive
    distant signals.
  • Armstrong also invented wide-band frequency
    modulation (FM) in 1935

3
  • Television, which was invented in the 1920s but
    didn't become widely available until 1947. (Bell
    Laboratories)
  • Vladimir Zworykin, an engineer with the Radio
    Corporation of America (RCA), is considered the
    "father of the television" because of his
    inventions, the picture tube and the iconoscope
    camera tube.
  • Radar ( RAdio Detection And Ranging,).
  • By the mid-1950s, television had surpassed radio
    for home use and entertainment.

4
  • In 1947, the transistor was invented by a team
    of engineers from Bell Laboratories. (Nobel
    prize)
  • The transistor functions like the vacuum tube,
    but it is tiny by comparison, weighs less,
    consumes less power, is much more reliable, and
    is cheaper to manufacture with its combination of
    metal contacts and semiconductor materials.

5
(No Transcript)
6
  • Integrated circuit was proposed in 1952 by
    Geoffrey W. A. Dummer, Throughout the 1950s,
    transistors were mass produced on single wafers
    and cut apart.
  • By 1961, integrated circuits were in full
    production at a number of firms, and designs of
    equipment changed rapidly and in several
    directions to adapt to the technology.
  • Bipolar transistors and digital integrated
    circuits were made first, but analog ICs,
    large-scale integration (LSI), and
    very-large-scale integration (VLSI) followed by
    the mid-1970s. VLSI consists of thousands of
    circuits with on-and-off switches or gates
    between them on a single chip.

7
  • Small Scale Integrated Circuits (SSI) Less than
    100 Transistors per Integrated Circuit or
    chipMedium Scale Integrated Circuits (MSI) 100
    to 1000 Transistors per Integrated Circuit or chip

8
  • Large Scale Integrated Circuits (LSI) 1000 to
    10000 Transistors per Integrated Circuit or chip
  • Very Large Scale Integrated Circuits (VLSI)
    10000 to 1 million Transistors per Integrated
    Circuit or chip

9
  • Ultra Large Scale Integrated Circuits (ULSI)
    over 1 million Transistors per Integrated Circuit
    or Chip

10
  • Microcomputers, medical equipment, video cameras,
    and communication satellites are only examples of
    devices made possible by integrated circuits.

11
Chapter 1
  • SEMICONDUCTORS

12
What is Electricity
  • Everything is made of atoms
  • There are 118 elements, an atom is a single part
    of an element
  • Atom consists of electrons, protons, and neutrons

13
  • When atoms lose or gain electrons, they become
    ions.
  • Cations are positive and are formed by elements
    on the left side of the periodic chart.
  • Anions are negative and are formed by elements on
    the right side of the periodic chart.

14
  • Valence electrons

15
  • Electrons (- charge) are attracted to protons (
    charge), this holds the atom together
  • Some materials have strong attraction and refuse
    to lose electrons, these are called insulators
    (air, glass, rubber, most plastics)
  • Some materials have weak attractions and allow
    electrons to be lost, these are called conductors
    (copper, silver, gold, aluminum)
  • Electrons can be made to move from one atom to
    another, this is called a current of electricity.

16
  • The controlled flow of charged particles is
    fundamental to the operation of all electronic
    devices
  • How do we distinguish semiconductors from
    insulators and conductors?
  • There are two principal charge transport
    processes
  • Drift motion of charges produced by an electric
    field
  • Diffusion motion resulting from a nonuniform
    charge distribution

17
FORCES, FIELDS AND ENERGY
  • Charged Particles
  • Charge of electron is ve 1.610-19 C
  • The mass of electron 9.1 10-31 kg
  • No. of electrons in 1 C 61018
  • 1pA is due to movement of 6 million electrons /
    sec
  • For ions the charge is a multiple of the electron
    charge but ve
  • The mass of an atom having atomic weight unity
    1.6610-27
  • The mass of any atom having atomic weight n
    n 1.6610-27

18
Field intensity
  • The charged particle exerts a force on other
    charged particles as given by Coulombs law
  • The motion of q2 is obtained by applying Newtons
    second law
  • The electric field intensity is the force exerted
    on a unit positive charge

19
Potential
  • Definition
  • In one dimension, with A at xo and B at an
    arbitrary distance x, it follows that
  • Differentiation
  • the potential energy U
  • If an electron is being considered, q is replaced
    by -q .
  • The electron volt (eV) unit of energy (work),
    defined as
  • 1 eV 1.60 x 10-19J

20
Energy
  • Law of conservation of energy
  • As an illustration of this law, consider two
    parallel plates A and B separated by a distance d
  • An electron leaves the surface of A toward B with
    an initial velocity vo in the x direction. What
    speed will the electron have if it reaches B?
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