The document provides an overview of multiplexers, specifically the 2x1 and 4x1 types, explaining their function as devices that select one input from multiple sources for output. It includes details on block diagrams, truth tables, timing diagrams, and real-time applications of multiplexers. Additionally, it offers examples and circuit diagrams for implementation, along with pricing for specific multiplexer models.

1. Balochistan
University Of
Information
Technology
Engineering and
Management
Sciences
Department of
Computer Engineering
Two Channels Multiplexer
or 2x1 Multiplexer
Atta Ullah Khan
43878@student.buitms.edu.pk
DIGITAL SYSTEM DESIGN
#000000

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Overview
 What is Multiplexer?
 Types of Multiplexer.
 Block Diagram of 2x1 and 4x1 Multiplexer.
 Timing Diagram of 2x1 Multiplexer.
 Real Time Multiplexer.
 Example of Two Channels Multiplexer?
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What is Multiplexer ?
 A multiplexer is a device which select one out of several
inputs & forward it to signal Output line.
 Multiplexer is also known as MUX.
 Multiplexer is also known as Data Selector. `
Remember in Multiplexer the number of output is always 1.
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Types of Multiplexer
 02:1 MUX,
 04:1 MUX,
 08:1 MUX,
 16:1 MUX,
 32:1 MUX.
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Block Diagram of Multiplexer
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Block
Diagram of
4 x 1
Multiplexer
Block
Diagram of
2 x 1
Multiplexer
S1
S2
SEL
S1
S2
S3
S4
U
U
SEL1
SEL2
Find Number of Input Lines
n = Selection lines
2n

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Truth Table of 2:1 Multiplexer
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Block
Diagram of
2 x 1
Multiplexer
S1
S2
SEL
U
SEL Output (U)
0 S1
1 S2
Logical Expression / Boolean Function
U = SEL . S1 + SEL . S2

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Timing Diagram of 2:1 Multiplexer
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Truth Table of 4:1 Multiplexer
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SEL1 SEL2 Output (U)
0 0 S1
0 1 S2
1 0 S3
1 1 S4
Logical Expression / Boolean Function
SOP = SEL1 . SEL2 . S1 + SEL1 . SEL2 . S2 + SEL1 . SEL2 . S3 + SE1 . SEL2 . S4
Block
Diagram of
4 x 1
Multiplexer
S1
S2
S3
S4
U
SEL1
SEL2

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Price: 30 Rs
8-Channel Analog
Multiplexer CD4051
Real Time Multiplexer
Price: 80 Rs
8 channel CMOS
Analog Multiplexer
DG408DY

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Circuit Diagram of 2:1 Multiplexer
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U = SEL · S1 · S2 + SEL · S1 · S2 + SEL · S1 · S2 + SEL · S1 · S2
U = (S1 · S2 + S1 · S2) · SEL + (S1 · S2 + S1 · S2) · SEL
U = ((S2 + S2) · S1) · SEL + ((S1 + S1) · S2) · SEL
U = S1 · SEL + S2 · SEL
Minimizing the Circuit
(S1 + S1) = 1,
(S2 + S2) = 1

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Circuit Diagram of 2:1 Multiplexer
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U = S1 · SEL + S2 · SEL
The Final Expression

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Implementation of 4:1 Multiplexer
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https://circuitdigest.com/tutorial/what-is-multiplexer-circuit-and-how-it-works

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MUX – Online Simulator
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Thank You
Have a Nice Day