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Multiplexer (MUX) DataSelectorA multiplexers (MUX) is a device

that allows digital information fromseveral sources to be routed onto asingle line for transmission overthat line to a common destination.

The basic multiplexers has severaldata input lines and a single

output line. It also has data selectinputs! which permit digital data onan" one of the inputs to beswitched to the output line

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Functional Diagram of aMUX

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Functional Diagram of aMUX A multiplexer has

control inputs

2!ata inputs

1 output (")

A multiplexer routes (or connects)the selecte! !ata input to the output#

$he %alue of the control inputs!etermines the !ata input that isselecte!#

#

$#

&

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MUX Function $a'le an!oolean xpression

Z = A.B'.I0+ A'.B.I1+ A.B'.I2+ A.B.I3

A B Z

0 0 I0

0 1 I1

1 0 I2

1 1 I3

MS *S

+

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MUX Function $a'le an!oolean xpression

Z = A.B'.C'.I0+ A'.B'.C.I1+ A'.B.C'.I2+ A'.B.C.I3+

A.B'.C'.I4+ A.B'.C.I5+ A'.B.C'.I6+ A.B.C.I7

MS *S

A B C Z

0 0 0 I0

0 0 1 I1

0 1 0 I2

0 1 1 I3

1 0 0 I4

1 0 1 I5

1 1 0 I6

1 1 1 I7

,

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MUX -utput .a%eforms in relation/ith the Data0nput an! Data0Select/a%eforms

The binary state of the

data-select inpts

drin! each inter"al

deter#ines $hich data

inpt is selected%&ere the data-select

inpts !o thro!h a

repetiti"e binary

se'ence00(01(10(11(00 and so

on%

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Designing logic circuit usingMUX

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Designing logic circuit usingMUX

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5asca!ing MUX

)sin! three 2-1 *)+to #a,e one 4-1 *)+

%& %' F

6 6 6

6 1 1

1 6 2

1 1 3

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5asca!ing MUX

%

$

%

&

%

'

F

6 6 6 6

6 6 1 1

6 1 6 2

6 1 1 31 6 6 &

1 6 1 +

1 1 6 ,

1 1 1

2-1

*)+

. /

.2

/

I0

I1

I2

I3

I4

I5

I6

I7

/a#ple Constrct an

-to-1 #ltipleer sin!2-to-1 #ltipleers%

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Demultiplexer 7 DMUX

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It re"erses the #ltiplein! fnction%

It ta,es data fro# one line and distribtes the#

to a !i"en n#ber of otpt lines% It is also

,no$n as a data distribtor%

A de#ltipleer ta,es a sin!le inpt and

distribtes it o"er se"eral otpts%

Compares to MUX : A #ltipleer ta,esse"eral inpts and trans#its one of the# to the

otpt%

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DMUX 7 Functional Diagram

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A !emultiplexer s/itches (or routes) !ata from oneinput to 2outputs8 /here is the num'er of selectinputs#

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DMUX 7 -utput .a%eforms

1&

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DMUX

1+

A B X ! Z

0 0 I 0 0 0

0 1 0 I 0 0

1 0 0 0 I 0

1 1 0 0 0 I

A%B%I

+ A%B%I

A%B%I

A%B%I

-ut6

n

S1 S6

I

+

A B

-ut1

-ut2

-ut3

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