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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. Boolean Algebra. Boolean Algebra B asic mathematics needed for the study of the logic design of digital systems
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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
Boolean Algebra • Boolean Algebra Basic mathematics needed for the study of the logic design of digital systems • George Boole developed Boolean algebra in 1847 • Solve problems in mathematics • Claude Shannon first applied Boolean algebra to the design of switching circuits in 1939
Boolean Algebra • Boolean Variable • Such as X or Y • Boolean Value or Constants • 0 , 1 • Basic Operations • AND, OR, and complement (or inverse)
Boolean Algebra • Basic Operations • AND, OR, and complement (inverse) • Complementation (Inversion)
Boolean Algebra • Basic Operations • AND, OR, and complement (inverse) • AND
Boolean Algebra • Basic Operations • AND, OR, and complement (inverse) • OR
Boolean Expressions and Truth Table • Boolean expressions • Formed by application of the basic operations to one or more variables or constants
Boolean Expressions and Truth Table • Boolean expressions • Evaluation
Boolean Expressions and Truth Table • Truth table (also called a table of combinations) • Specifies the values of a Boolean expression for every possible combination of values of the variables in the expression • 2n rows for n input variables
Basic Theorems • Involve single variable
Commutative, Associative and Distributive laws • Commutative (جا به جایی) • Associative (شرکت پذیری) • Distributive (توزیعی) XY = YX X+Y = Y+X (XY)Z=X(YZ)=XYZ (X+Y)+Z = X+(Y+Z) = X+Y+Z X(Y+Z) = XY + XZ X + YZ = (X+Y)(X+Z)
C B G A Logic Optimization C F A F=A’ + B•C’ + A’•B’ B G=A’ + B•C’
Multiplying out and Factoring • Multiplying out • Forming SOP Sum Of Products • Factoring • Forming POS Products Of Sum
DeMorgan’s Law • DeMorgan’s Laws • Proof • Generalized Laws
DeMorgan’s Law • DeMorgan’s Laws • Example
Dual • Replacing AND with OR, OR with AND • Replacing 0 with 1, 1 with 0 • Variables and complements are left unchanged
Exclusive-OR XOR • Theorems • Proof of distribution law
Equivalence Exclusive-NOR XNOR • Example
Consensus Theorem (قانون اجماع) • Theorem • Proof • Dual
Algebraic Simplification • Combining terms • XY + XY’ = X • Eliminating terms • X + XY = X • Eliminating literals • X + X’Y = X+Y
Algebraic Simplification • Example
Proving Validity of an Equation • Construct a truth table and evaluate both sides • Manipulate one side of the equation by applying various theorems until it is identical with the other side • Reduce both sides of the equation independently to the same expression • It is permissible to perform the same operation on both sides of the equation provided that the operation is reversible. For example, it is all right to complement both sides of the equation
Proving Validity of an Equation Example