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Lecture-0 - IntroductionDigital Electronics

Dr. Sajid Muhaimin ChoudhuryDept of EEE, BUET

EEE 303 – Digital Electronics

• Course Teacher: Dr. Sajid Muhaimin Choudhury (Section A and B)

• Email Address: sajid@eee.buet.ac.bd

• Course Website: http://sajid.buet.ac.bd/teaching/J2020_EEE303

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Office Hours

• Tues 12-1pm (Section A)• Saturday 12-1pm (Section B)

• I will be in my office at EEE 222, and students are welcome to drop by with any questions/problems related to the class or for conceptual understanding of the topics.

• Preferred medium of communication: email

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Learning Objectives

• To gain insights into digital logic circuit design

• To gain skills to simulate and verify digital logic circuits

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Grading

• 10% - Class performance and attendance• 20% - Quiz: best 3 out of 4 quiz. Each quiz

will be of 20 marks. 10 marks homework, and 10 marks class test of 10 minutes

• 70% - Term final

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Textbooks

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Concept of Digital

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Digital Electronics

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Continuous vs Discrete

Continuous Variable• Defined continuously

in time

Discrete Variable• Discrete Time• Discrete Value

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Digital System

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Discrete Information Processing

System

Discrete Output

Discrete Input

System States

Takes discrete input, has discrete system states and gives discrete output

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Information Representation

• Information variables are represented by physical quantities (voltage, current, charge, magnetic field orientation, temperature, phase)

• For digital systems, the variables take discrete values

• Two level or binary values are most common

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Signals over Time

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Time

Analog

Digital

Synchronous

Asynchronous

Types of Digital Systems

• No state Present, Output = f(input)• Combinational logic system

• State Present, Output = f(input, state)• Synchronous Sequential System (state

updated at discrete times)• Asynchronous Sequential System

(state updated at any time)

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Digital System Example

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Digital clockInput: Time setOutput: Current timeState: Current time

Digital computerCovered in EEE 416

Binary representation of physical quantities• CPU: Voltage• HDD: Magnetic Field Direction• CD: Physical shape of pits• DRAM: Electric Charge• Optical Fiber: Light intensity

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Summary

• Difference between analog and digital

• Next class: number systems

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