Digital Electronics

1. Welcome
COURSE NAME: DIGITAL ELECTRONICS II
COURSE CODE: ECE-213

2. Submission Details
Submitted by,
Group D
Akhinur Nahar Smrity - 53
Israt Faria Emi - 58
Abdullah Al Fahim - 63
2nd Year, 4th Semester, Dept of ECE
Institute of Science Trade & Technology (ISTT)
Submitted to,
Md Robiul Islam
Sr. Lecturer, Dept. of ECE
Institute of Science Trade & Technology (ISTT)
Topic Name: Multiplexer & Demultiplexer
Submission Date: 20 August 2020

3. Group D Team Members Details:
Akhinur Nahar Srity
ID: 53
Session: 2017-18
Israt Faria Emi
ID: 58
Session: 2017-18
Abdullah Al Fahim
ID: 63
Session: 2017-18
2nd Year, 4th Semester
Department of Electronics & Communication Engineering
Institute of Science Trade & Technology (ISTT)

4. Objectives
The purpose of this presentation is to gather
understandable knowledge to design basic
Multiplexer and Demultiplexer combinational
circuits and to implement them into a data
transmission system.

5. Introduction:
Today we’ll discuss on this contents of Multiplexer & Demultiplexer:
1. Definition
2. Types
3. Truth Table
4. Equations
5. Circuit Diagrams
6. Applications & Used
7. Advantages & Disadvantages

6. Multiplexer
Multiplexer (MUX) is a combinational circuit that selects binary
information from one of many input lines and directs it to single
output lines. So, it is simply called a data selector.
Fig: Functional Diagram of MUX

7. Types of Multiplexer
There are many types of Multiplexer. Such as,
1. Two (2) input MUX
2. Four (4) input MUX
3. Eight (8) input MUX
4. Sixteen (16) input MUX

8. 2 to 1 Multiplexer Diagram, Truth table & Equations:
S’ S Z
0 * 0
1 0 I0
1 1 I1
Truth Table
S
S’
I0
I1
Equation:
Z = I0 S’ + I1 S
Z = I0 S’ + I1 S
Fig: Diagram of 2 input MUX

9. 4 to 1 Multiplexer Diagram, Truth table & Equations:
S0 S1 Z
0 0 I0
0 1 I1
1 0 I2
1 1 I3
Truth Table
Fig: Diagram of 4 input MUX
Equation:
Z = I0S0’S1
’ + I1 S0’S1 + I2 S0 S1
’ + I3 S0 S1
S0 S1
Z

10. Application & Used of Multiplexer:
1. Communication System
2. Computer Memory
3. Telephone Network
4. Transmission from the computer system of a satellite

11. Advantages & Disadvantages of Multiplexer:
Advantages:
1. It reduces circuit complexity and cost.
2. Implementation of various Circuits using mux.
3. It does not need K-maps and simplification.
Disadvantages:
1. Added delays in switching ports.
2. Limitations on which ports can be used simultaneously.

12. Demultiplexer
Demultiplexer (or DEMUX) is a device that takes a single input line
and routes it to one of several digital output lines. That means it is a
reverse operation of MUX and it is called data distributor .
Fig: Functional Diagram of DEMUX

13. Types of Demultiplexer
There are many types of Demultiplexer. Such as,
1. 1 line to 2 line DEMUX
2. 1 line to 4 line DEMUX
3. 1 line to 8 line DEMUX

14. 1 to 8 Demultiplexer, Truth Table & Equations:
Truth Table
Fig: Diagram of 8 output DEMUX
= D(S2’S1’S0’)
= D(S2’S1’S0)
= D(S2’S1S0)
= D(S2S1’S0’)
= D(S2S1‘S0)
= D(S2S1S0’)
= D(S2S1S0)
= D(S2’S1S0’)

15. Applications & Used of Demultiplexer:
1. Communication System
2. Arithmetic Logic Unit
3. Serial to Parallel Converter

16. Advantages & Disadvantages of Demultiplexer:
Advantages:
1. Also used as decoders in security system like banking
sectors
2. Increases the efficiency of the communication system
Disadvantages:
1. Wastage of bandwidth might occur
2. Delays might occur due to synchronization of signals

17. Questions From Teachers….!!!

18. THANK YOU