chapter 01

In the name of Allah, the Most Gracious the Most Merciful

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ELECTRONICSLecture No.01

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Course Outline

Part-1 (25%)

Semiconductors, rectifiers, transistors, relays, Operational

Amplifiers.

Part-2 (75%)

Number systems, Boolean Algebra, gates. Combinational logic

(adders, comparators, decoders, multiplexers, etc.) Sequential

logic (flip-flops, registers, counters, ROM, PROM, EPROM).

Microprocessors (registers, ALU, CU, memory, address, data and

control buses). ADC and DAC. Micro-controllers

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Recommended Books1. Electronic Devices by Floyd, 7th Edition, Prentice hall

2. Digital Design by M. Morris Mano & Michael D. Ciletti , 4th

edition

3. Electronic Principles By Malvino, A.Paul, McGraw Hill

4. Digital Computer Electronics 2nd Edition , By Malvino , McGraw

Hill 

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Grading Policy Sessionals (30%)

Class assignments Chapter end problems

Quizzes Project

Mid-Semester Exam (20%) End-Semester Exam (50%) Lab Sessionals (15%) Lab Viva (10%)

(75 %)

(25 %)

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SEMICONDUCTOR BASICS

Friday, April 7, 2023

CHAPTER NO. 01

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Objectives

Discuss the basic structure of atoms

Discuss semiconductors, conductors, and insulators

Discuss covalent bonding in silicon

Describe how current is produced in a semiconductor

Describe the properties of n-type and p-type semiconductors

Describe a diode and how a pn junction is formed

Discuss the bias of a diode

Analyze the voltage-current (V-I) characteristic curve of a diode

Discuss the operation of diodes and explain the three diode models

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Atomic Structure

An atom is the smallest particle of an element that retains the

characteristics of that element , which gives each element a unique

atomic structure

All matter is made of atoms and all atoms consist of electrons, protons,

and neutrons

The Bohr model of an atom showing electrons in orbits around the

nucleus, which consists of protons and neutrons. The "tails" on the

electrons indicate motion can be pictorially shown in the next slide

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Bohr model of an atom

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Two Simplest Atoms (Hydrogen &

Helium)

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Energy level increases as the distance from the

nucleus increases

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Diagram of carbon atom

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Energy bands of three types of

materials

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Diagram of silicon and copper atoms

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Diagram of silicon and germanium

atoms

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Illustration of covalent bond in silicon

atom

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Energy band diagram of a pure silicon

atom

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Creation of Electron-Hole pair in a

silicon crystal

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Illustration of Electron Hole pair (Generation &

Recombination)

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Electron current in intrinsic silicon

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Hole current in intrinsic silicon

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Pentavalent impurity atom in a silicon

crystal structure

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Trivalent impurity atom in a silicon

crystal structure

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Basic diode structure

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Formation of the Depletion region

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Energy diagrams illustrating the formation of PN

junction and depletion region

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Diode connected with forward bias

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Voltage due to the barrier potential across the

depletion region

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Depletion region narrows and voltage

drops when diode is forward bias

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Diode connected with reverse bias

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Diode after reverse voltage is applied

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Small reverse current in a reverse

bias diode

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VI characteristic curve for a diode

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Diode structure and schematic

symbol

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Forward & Reverse bias connection

of a diode

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DIODE MODELS

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Ideal model of a diode

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Practical model of a diode

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Complete model of a diode

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Example:

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Solution:

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Solution: (contd…)

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