Different Logic Gates

Logic gates are the general purpose electronics devices which have a specific o/p state for diffferent combinations of input.

Different types of Logic gates:-

1. AND Gate

 
Symbol 
 

Truth table     

INPUT		OUTPUT
A	B	A AND B
0	0	0
0	1	0
1	0	0
1	1	1

Relationship between inputs and output

Output = A and B
                  or
                A.B
=========================================================


2. OR Gate


Symbol


Truth table

INPUT		OUTPUT
A	B	A OR B
0	0	0
0	1	1
1	0	1
1	1	1

Relationship between inputs and output

Output =    A or B

                    or

                  A+B

===========================================================

3. NOT gate

Symbol

Truth Table

INPUT	OUTPUT
A	NOT A
0	1
1	0

Relationship between inputs and output

Output =  Not A

                    or

                    

=============================================================

4.NOR gate

Symbol

Truth Table

INPUT		OUTPUT
A	B	A NOR B
0	0	1
0	1	0
1	0	0
1	1	0

Relationship between inputs and output

Output = Not(A OR B)

                         or 

                    

===========================================================

5.NAND gate

Symbol

Truth table

INPUT		OUTPUT
A	B	A NAND B
0	0	1
0	1	1
1	0	1
1	1	0

Relationship between inputs and output

Output =  Not (A AND B)

                           or

                       

============================================================

6. XOR gate

Symbol

Truth Table

INPUT		OUTPUT
A	B	A XOR B
0	0	0
0	1	1
1	0	1
1	1	0

Relationship between inputs and output

Output  =   [ A AND (NOT B) ] OR [ (NOT A) AND B ]

                                                    or

                                              

==============================================================

7. XNOR gate

Symbol

Truth Table

INPUT		OUTPUT
A	B	A XNOR B
0	0	1
0	1	0
1	0	0
1	1	1

Relationship between inputs and output

Output = [ A AND B] OR [ (NOT A) AND (NOT B)]

                                     or

                       or 

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