SILVER OAK COLLEGE OF
ENGINEERING AND TECHNOLOGY
TOPIC :STUDENT NAME :- SIDDHI SHRIVAS
(130770107163)
DIVISON :- COMPUTER – C
GUIDED BY :-MR. BIKAS MUDULI, SOCET
 WHATIS MULTIPLEXER?
o
A MULTIPLEXER is a digital circuit that has multiple inputs and asingle
output.
o
The selection of one of the n inputs is done by the select inputs
o
It has one output selected at a time.
o
It is also known as DATA SELECTOR.
o
A multiplexer has
N
data inputs(multiple)
1
output(single)
 Mselect inputs, with 2M =N
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 BLOCKDIAGRAMOFMULTIPLEXER:
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 Types:

2-to-1 (1 selectline)

4-to-1 (2 select lines)

8-to-1 (3 select lines)

16-to-1 (4 select lines)
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 2-TO-1(1SELECTLINES)MULTIPLEXER
Here 2:1 means 2 inputs and 1 output
BLOCK DIAGRAM
MULTIPLEXER
TRUTH TABLE
S
OUTPUT Y
0
D0
1
D1
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
The logical level applied to the S input determines which AND gate is
enabled, so that its data input passes through the OR gate to the output.

The output, Y=D0S’+D1S

When

S=0,AND gate 1 is enabled and AND gate 2 is disabled. So, Y=DO

S=1,AND gate 1 is disabled and AND gate 2 is enabled . So,Y=D1
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 4-to-1(2selectlines)Multiplexer

4:1 MUXhas 4 inputs(D0, D1, D2, D3) & 2 select lines(S0, S1)
BLOCK DIAGRAM
TRUTHTABLE
D1
D2
MUX
D0
D3
S1
MULTIPLEXER
S0
Y
S1
S0
Y
0
0
D0
0
1
D1
1
0
D2
1
1
D3
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
The logical level applied to the S input determines which AND
gate is enabled, so that its data input passes through the OR
gate to the output.

The output, Y=S1’S0’D0+S1’S0D1+S1SO’D2+S1S0D3
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 8-TO-1(3SELECTLINES)MULTIPLEXER

8:1 MUXhas 8 inputs(D0, D1, D2, D3, D4, D5, D6, D7) & 3
select lines(S0,S1, S2,)
BLOCK DIAGRAM
MULTIPLEXER
TRUTH TABLE
S2
S1
S0
Y
0
0
0
D0
0
0
1
D1
0
1
0
D2
0
1
1
D3
1
0
0
D4
1
0
1
D5
1
1
0
D6
1
1
1
D7 9
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
The logical level applied to the S input determines which AND
gate is enabled, so that its data input passes through the OR
gate to the output.
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 UsesofMultiplexers

Used in data communications for several computers to
communicate over 1 line

Used in radio to select one channel from many

Used to route data within a computer

Used for function generation
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 APPLICATIONOFMULTIPLEXER:
Multiple Sources
Selector
Single Destination
MP3 Player
Docking Station
Laptop
Sound Card
D1
D2
MUX
D0
Y
D3
Surround Sound System
Digital
Satellite
MULTIPLEXER
Digital
Cable TV
B
A
Selected Source
0
0
MP3
0
1
Laptop
1
0
Satellite
1
1
Cable TV
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EXAMPLEOFACOMBINATORIALCIRCUIT:
AMULTIPLEXER(MUX)
Consider an integer ‘m’, which isconstrained by the following relation:
m = 2n,

where m and n are both integers.
Am-to-1 Multiplexer has
 m Inputs: I0, I1, I2, ................ I(m-1)
 one Output: Y
 n Control inputs: S0, S1, S2, ...... S(n-1)
 One (or more) Enable input(s)
such that Y may be equal to one of the inputs, depending upon the
control inputs.
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ImplementingDigitalFunctions:
byusingaMultiplexer:
In this example to design a 3 variable logical function, we try to
use a 4-to-1 MUXrather than a 8-to-1 MUX.
F(x, y, z)=∑ (m(1, 2, 4, 7)
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ImplementingDigitalFunctions:
byusingaMultiplexer:continue……
In a canonic form:
F = x’.y’.z+ x’.y.z’+x.y’.z’ +x.y.z
…… (1)
One Possible Solution:
Assume that x = S1 ,
y = S0 .
If F is to be obtained from the output of a 4-to-1 MUX,
F =S’1. S’0. I0 + S’1. S0. I1 + S1. S’0. I2 + S1. S0. I3 ….(2)
From (1) and (2),
I0 = I3 =Z
MULTIPLEXER
I1 = I2 =Z’
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ImplementingDigitalFunctions:
byusingaMultiplexer:continue……
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ImplementingDigitalFunctions:
byusingaMultiplexer:continue……
Another Possible Solution:
Assume that z =S1 ,
x = S0 .
If F is to be obtained from the output of a 4-to-1 MUX,
F = S’0 .I0 . S1 + S’0 .I1 . S’1 + S0 .I2 . S’1 + S0 .I3 . S1
From (1) and (2),
………… (3)
I0 = y’ =I2
I1 = y =I3
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ImplementingDigitalFunctions:
byusingaMultiplexer:continue……
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THANK YOU
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