The Night Sky

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DIGITAL ELECTRONICS
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DIGITAL ELECTRONICS
Digital Logic

• Everything in digital world is based on binary
  system.
• Numerically it involves only two symbols
• 0 or 1.
• 0 False No
• 1 True Yes
• Binary Number System Easy to design stable
  electronic circuits.

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DIGITAL ELECTRONICS
Boolean Algebra

• Digital circuits need to be as simple as
  possible.
• Complex logical expressions should be reduced to
  simpler expressions, however, produce same
  results under all conditions.
• Benefit Simpler expressions can be implemented
  with simpler circuits, which are cost effective.

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DIGITAL ELECTRONICS
Boolean Algebra

• Mathematics of logical expression is the tool to
  reduce the complicated expressions.
• Introduced by George Boole in 1854 and known
  today as Boolean Algebra.
• The rules of Boolean Algebra is simple and
  straightforward, can be applied to any logical
  expression.

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DIGITAL ELECTRONICS
Boolean Algebra

• For two binary variables (taking 0 and 1), there
  are 16 possible functions.
• These functions involve only three operations

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DIGITAL ELECTRONICS
16 Functions
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DIGITAL ELECTRONICS
Boolean Algebra Theorems
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DIGITAL ELECTRONICS
Gates

• Gates are fundamental building blocks of digital
  logic circuitry.
• These devices operate by closing or opening
  to admit or reject the passage of logical signal.

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DIGITAL ELECTRONICS

• Basic gate types are
• AND
• OR
• XOR
• NOT
• A vast array of gating functions can be created
  from these basic gates.

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DIGITAL ELECTRONICS

• The AND Gate

Truth Table
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DIGITAL ELECTRONICS
The AND Gate
Truth Table
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DIGITAL ELECTRONICS
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