DIGITAL LOGIC

TRUTH TABLE

How to know the number of entries ?

Truth table with n input contain 2^ (n) entries

 >> For example : : input = 3 , so the number of entrries = 2^(3) = 8

INPUT			OUTPUT
A	B	C	D
0	0	0	0
0	0	1	0
0	1	0	0
0	1	1	0
1	0	0	0
1	0	1	0
1	1	0	0
1	1	1	1

          >> example of truth table with 3 input and [  (A . B .C) = D ]  

by : siti nazirah

BOOLEAN ALGEBRA

‘OR’ is written as ' + '

‘AND’ is written as ' . ' / / ' &'

‘OR’ is written as ' + '

BOOLEAN ALGEBRA LAWS

LAWS
IDENTITY LAW	A + 0 = A	A & 1 = A
ZERO AND ONE LAWS	A + 1 = 1	A & 0 = 0
INVERSE LAW	A + A’ = 1	A & A’ = 1
COMMUTATIVE LAWS	A + B = B + A	A & B = B & A
ASSOCIATIVE LAWS	A + (B + C) = (A + B) + C	A & (B & C) = (A & B) & C
DISTRIBUTIVE LAWS	A & (B + C) = (A & B) + (A & C)	A + (B & C) = (A + B) & (A + C)

by : nor izzati

GATES 

AND gate [A & B = Q]

OR gate [A + B = Q]

NOT gate [ A'  = Q]

NAND gate

NOR gate

by :  robael adawiyah

SUM OF PRODUCT

>> logical sum of products ( OR ) which terms using AND operator <<

example : E = (A & B & C) + ( A' & B & C) + ( A + B' + C')

From the truth table , we have to choose combination of input values that produce 1's only !

by : wan nur ulaiya


PRODUCT OF SUM

>> logical products of sum ( AND ) which terms using OR operator <<
    { opposite to sum of product }

example : E = (A + B + C) & (A' + B + C) & (A + B' + C')

From the truth table , we need to choose combination of input values that produce 0's only !

by : siti hajar

source : lecture note chapter 4_5 The Basic of Logic Design BITS 1123 FTMK UTeM