HALF ADDER AND FULL ADDER

HALF ADDER

            Half adder is like a small circuit that performs an addition tasks on only two inputs 0 and 1 for each input and gives us two outputs one is sum and the second is carryout number. Which consist of and exclusive OR gate that and AND gate including two inputs, where X-OR gate perform Sum and AND gate gives carry out number, which is more explain by logic diagram, logic symbol and truth table.

LOGIC DIAGRAM

half adder logic diagram

            

           Where the A and B is input and Sum = AÅB output of XOR and the Carry out number is A x B output of AND gate.

LOGIC SYMBOL:

halfadder logic symbol

TRUTH TABLE

A	B	AÅB	A x B
0	0	0	0
0	1	1	0
1	0	1	0
1	1	0	1

 FULL ADDER

            Process is same like half adder that perform addition and full adder also perform addition where the main difference between them is the number of input, where half adder have only two input and full adder have three inputs A, B and Cin. It also has two outputs one is sum and second is carryout number. See the logic diagram, logic symbol and truth table for understand to deep.

LOGIC SYMBOL 

fulladder logic diagram

          In this series three inputs are A, B and Cin where the final results are Sum and Carryout number as shown in figure. In full adder we used 5 gates two AND gate two XOR gate and one OR gate.

LOGIC SYMBOL

            Arrangement of two half adder to form a full adder in such a way that it look like as show

full adder logic symbol

TRUTH TABLE

Inputs	Outputs
Cin A B 0 0 0 0 0 1 0 1 0 0 1 1 1 0 0 1 0 1 1 1 0 1 1 1	Sum Carryout 0 0 1 0 1 0 0 1 1 0 0 1 0 1 1 1