MUX
MULTIPLEXER
MULTIPLEXER
• Other Names;
i) MUX
ii) Data Selector
iii) Electronic Rotary Switch
iv) One package Solution for Logic Problem
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Multiplexer
• Multiplex means ‘many into one’
• Multiplexing is the method of transmitting a
large number of information over a small
number of channels or lines and a Digital
Multiplexer is a combinational Logic circuit
that selects binary information from one of the
many input lines and directs it to a single
output line.
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MULTIPLEXER
• Multiplexer is an electronic circuit that has
maximum of 2ⁿ Data inputs, ‘n’ Control inputs
(or selection lines) and single Output.
By the help of control inputs any one of the
data inputs can be selected at a time and
whatever the data, logic or signal applied on it
can be transferred to the output
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MULTIPLEXER
• ‘MUX’ is the short name of Multiplexer
• As data from several sources can be applied to the inputs of
MUX and only one of them can be selected and routed to the
out, it’s also called as ‘Data Selector’
• It’s function is like a mechanical rotary switch where among
multiple positions any one can be selected by rotating the
switch to that position, that’s why is also known as ‘Electronic
Rotary Switch’
• A single MUX IC can replace a logic circuit made up of
multiple I.Cs, that is why it is given the name ‘One Package
solution of Logic Problem’
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MULTIPLEXER BLOCK DIAGRAM
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Selection Table
of a 4 x 1 MUX
Control or Selection
Inputs
O/P
S1
S0
Y
0
0
I0
0
1
I1
1
0
I2
1
1
I3
Block diagram of 8x1 Multiplexer
by using two 4x1 MUX & a 2x1 MUX
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Selection Table
of a 8 x 1 MUX
When S2 is 0 lower MUX (say MUX 0) is selected) &
When S2 is 1 upper MUX (say MUX 1) is selected.
So if S2 is 0 and S0 & S1 have 00 inputs then Input I0 comes on
output and so on.
O/P
Control or Selection Inputs
S2
S1
S0
Y
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
MULTIPLEXER CIRCUIT
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MULTIPLEXER CIRCUIT
• 2 x 4 MUX (Matrix)
• This equation can be implemented in form of Gates as shown
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74150 IC 16 x 1 MUX Internal Circuit
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