The document provides an overview of digital adders, which are circuits that perform binary addition. It details the types of adders, specifically half adders and full adders, explaining their functions and outputs. The text includes equations and truth tables relevant to the operation of these adders in digital circuits.

1. Adder
PREPAREDBY:
Mahfuzur RahmanFaruk
ID : 181002057
Sec : DB
Green University OF Bangladesh
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2. 2
CONTENTS
• Introduction
• Adder means
• Types of adders
 Half adder
 Full adder
 Ripple carry adder

3. 3
INTRODUCTION
• Digital computers perform various arithmetic operation
Basic arithmetic operation is addition of two binary digits.
• The first three operations produce a sum whose length is
one digit but when the last operation is performed sum is
two digits. The higher bit is called carry. And lower bit is
called sum. This operation is called half adder. The circuit
which performs addition of three bits is a fulladder.

4. 4
ADDERMEANS???
• An adder is a digital circuit that performs additionof
numbers.
• Inprocessor it is used to calculate addresses, table indices,
and similar operations.
• It can be constructed for many numerical representations,
such as binary-coded decimal the most common adders
operate on binary numbers.

5. 5
TYPESOFADDERS
• Half adder
• Full adder

6. HALFADDER
The half adder adds two single
binary digits Aand B.
It has two outputs, sum (S) and carry
(C).
Sum=AB’+A’B.
Carry=A*B.
For half-adder design,
an XORgate & an ANDgate
TRUTHTABLE
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7. FULLADDER
Acombinational circuit that adds 3 input bits to generatea
Sumbit and a Carry bit
Where X,Y,Zare inputs and C& Sareoutputs.
Sum= X+Y+Z.
Cout=XY’+YZ’+ZX’.
TRUTHTABLE
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X Y Z S C
0 0 0 0 0
0 0 1 1 0
0 1 0 1 0
0 1 1 0 1
1 0 0 1 0
1 0 1 0 1
1 1 0 0 1
1 1 1 1 0

8. THANKYOU
115/1/2016