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Digital Logic & Design

Dr. Sajjad Ahmed Nadeem

Department of Computer Science & IT University of Azad Jammu & Kashmir

Muzaffarabad

Module - 6

� Canonical and Standard Forms.

� SOP and POS.

� NAND and NOR Gates.

� Exclusive OR Function.

� Equivalence Function.

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Canonical and Standard Form

� Minterms For a boolean function of n variables , a product term in which each of the variables appears once (in either its complemented or uncomplemented form) is called a minterm.

� Maxterms For a boolean function of n variables , a sum term in which each of the variables appears once (in either its complemented or uncomplemented form) is called a maxterm.

Canonical and Standard Form

� Boolean functions expressed as a sum of minterms or product of maxterms are said to be in canonical form.

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Canonical and Standard Form

Minterms and Maxterms for three binary variables

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Sum of Products (SoP) Expression

Steps to express a Boolean Function in SOP Form

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Expressing a Boolean Function in SOP Form - Example

Expressing a Boolean Function in SOP Form - Example

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Product of Sums (PoS) Expression

Steps to express a Boolean Function in POS Form

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Expressing a Boolean Function in POS Form - Example

Expressing a Boolean Function in POS Form - Example

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Conversion between Canonical Forms (Sum of Products and Product of Sums)

NAND Gate

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NAND Gate

NOR Gate

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NOR Gate

Logic Gates

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Finding Booloean Expression of a Logic Circuit – Example 1

Finding Booloean Expression of a Logic Circuit – Example 1

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Finding Booloean Expression of a Logic Circuit – Example 2

Finding Booloean Expression of a Logic Circuit – Example 2

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Constructing a Logic Circuit from Boolean Expression – Example 1

Constructing a Logic Circuit from Boolean Expression – Example 1

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Constructing a Logic Circuit from Boolean Expression – Example 2

Constructing a Logic Circuit from Boolean Expression – Example 2

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Exclusive-OR Function

Exclusive-OR Function

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Equivalence Function

Equivalence Function