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طراحی مدارهای منطقی. دانشگاه آزاد اسلامی واحد پرند. نیمسال دوم 92-93. طراحی مدارهای منطقی. دانشگاه آزاد اسلامی واحد پرند. جبر بول 2 . Contents. Combinational Logic Design Conversion of English Sentences to Boolean Equations Using a Truth Table Minterm and Maxterm Expansions
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طراحی مدارهای منطقی دانشگاه آزاد اسلامی واحد پرند نیمسال دوم 92-93
طراحی مدارهای منطقی دانشگاه آزاد اسلامی واحد پرند جبر بول 2
Contents • Combinational Logic Design • Conversion of English Sentences to Boolean Equations • Using a Truth Table • Minterm and Maxterm Expansions • Incompletely Specified Functions • Examples of Truth Table Construction
Conversion of English Sentences to Boolean Equations • The three main steps in designing a single-output combinational switching circuit are • Find a switching function that specifies the desired behavior of the circuit • With or Without Truth Table • Find a simplified algebraic expression for the function • Realize the simplified function using available logic element
Conversion of English Sentences to Boolean Equations • Examples (Without Truth Table) F = A . B Z = A.B’ + CD’
Conversion of English Sentences to Boolean Equations • Examples (With Truth Table) • f = 1 if N≥ 0112 and • f = 0 if N < 0112
Minterm and Maxterm Expansions • Minterms and Maxterms for Three Variables
Minterm and Maxterm Expansions • Standard (Canonical) SOP Minterm Expansion • Standard (Canonical) POS Maxterm Expansion
Minterm and Maxterm Expansions • Finding Minterm Expansion • Using X + X’ = 1
Minterm and Maxterm Expansions • Finding Maxterm Expansion • Using XX’ = 0
Minterm and Maxterm Expansions • Relation Between F and F’
Incompletely Specified Boolean Functions Don’t Care Minterms • Example • There is no output ABC=001 and 110 • Both 0 • First 1, Second 0 • Both 1
Incompletely Specified Boolean Functions Don’t Care Minterms • Example • There is no output ABC=001 and 110
Examples of Truth Table Construction • 1-bit binary adder adds two 1-bit binary numbers
Examples of Truth Table Construction • 2-bit binary adder adds two 2-bit binary numbers
Examples of Truth Table Construction • Input (A, B, C, D) represent 8-4-2-1 binary-coded-decimal digit. • Output (Z) is 1 iff the decimal number represented by the inputs is exactly divisible by 3. • Only valid BCD digits occur as inputs. • 0 0000 • 3 0011 • 6 0110 • 9 1001