digital electronics

1. Digital Electronics
Presentation on
Lecture1 : Introduction to Digital
Electronics
Presented By :
Parag Parandkar
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Presentation on
Lecture1 : Introduction to
Digital Electronics
Presented By :
Parag Parandkar

2. Contents
 Analog vs. Digital
 Why Digital or Analog?
 Advantages of digital over analog
 How to get digital from analog
 How its made
 Where are they used
 How do they look
 What’s inside
 Levels of integration
 Digital design as Logic Circuits and its applications
 Number System and Interconversions
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3. Analog vs. Digital
Analog signal- one whose output varies continuously in step
with the input.
Example:
Analog
Analog
Digital signal- one whose output varies at discrete voltage levels
commonly called HIGH or LOW (1 or 0).
Example:
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4. Why Digital?
Data can be stored (memory characteristic of digital).
Data can be used in calculations.
Compatible with display technologies.
Compatible with computer technologies.
Systems can be programmed.
Digital IC families make design easier.
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5. Why Analog?
Most “real-world” events are analog in
nature.
Analog processing is usually simpler.
Analog processing is usually faster.
Traditional electronic systems were
mostly analog in nature.
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6. Benefits of Digital over Analog
Reproducibility
Not effected by noise means quality
Ease of design
Data protection
Programmable
Speed
Economy
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7. How to get Digital from Analog?
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 SAMPLING

8. How its made?
8
 At any point in the circuit, only two Voltage states are
present- HIGH or LOW.
 Also sometimes called TRUE or FALSE. In Boolean
Logic, 0 and 1.
 Generally, +5V (roughly) considered high, while
0V(ground) is considered low.
 Transistor as a switch is the building block of Digital Electronics

9. Where are they used?
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 Think of any Real Life Application of Logic Gates!
• What are the
inputs?
• What’s the
output?
• Which logic gate
should be used?

10. How do they look?
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“SN74LS00” WHAT’S THIS??

11. What’s Inside?
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Pin Diagram of SN74LS00 NAND IC

12. Complexity in a digital design
Complexity can, and generally does,
surpass human capability.
– 10-100 million transistors/cm2 now.
– 100-1000 million transistors/cm2 in 10
years.
Provides motivation for computer-based
design techniques.
Most engineering work is done with CAD
packages.
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13. Levels of Integration
Integration levels
SSI (small scale integration)
Introduced in late 1960s
1-10 gates (previous examples)
MSI (medium scale integration)
Introduced in late 1960s
10-100 gates
LSI (large scale integration)
Introduced in early 1970s
100-10,000 gates
VLSI (very large scale integration)
Introduced in late 1970s
More than 10,000 gates
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14. Digital Circuits
 A digital circuit is often constructed from small electronic
circuits called logic gates that can be used to create
combinational logic. Each logic gate represents a function of
boolean logic.
 A logic gate is an arrangement of electrically controlled
switches, better known as transistors.
 The output of a logic gate is an electrical flow or voltage, that
can, in turn, control more logic gates.
 Integrated circuits are the least expensive way to make logic
gates in large volumes.
 Another form of digital circuit is constructed from PLD for
small volume.
 When the volumes are medium to large, microcontroller is
programmed to make an embedded system. These are usually
programmed by software engineers.
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15. Application of logic circuits
This slide is adapted from freely available slides of shantanu dutt.
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16. This slide is adapted from freely available slides of shantanu dutt.
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17. The role of logic
This slide is adapted from freely available slides of shantanu dutt.
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18. This slide is adapted from freely available slides of shantanu dutt.
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19. This slide is adapted from freely available slides of shantanu dutt.
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20. This slide is adapted from freely available slides of shantanu dutt.
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21. This slide is adapted from freely available slides of shantanu dutt.
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22. This slide is adapted from freely available slides of shantanu dutt.
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