This document discusses encoders. It defines an encoder as a device, circuit, transducer, software program, algorithm, or person that converts information from one format to another. It provides examples of different types of encoders, including: - Binary encoders, which have 2n inputs and n outputs, with one of the 2n inputs set to 1 and the output being an n-bit binary number. - Linear encoders, which are sensors with a scale that encodes position and converts the encoded position into an analog or digital signal. - Digital encoders, also called binary encoders, that take data inputs one at a time and convert them into a single encoded output. Common configurations include 4

2. Name :
Ms. Most. Hasna Hena
Designation :
Senior Lecturer , DIU
Department :
Department of Computer Science and Engineering
Faculty :
Faculty of Science and Information Technology
Personal Webpage :
http://faculty.daffodilvarsity.edu.bd/profile/cse/hena.html
E-mail :
hena.cse@diu.edu.bd

5. Defination of Encoder
 The encoder is a combinational circuit that performs the reverse operation
of the decoder. The encoder has a maximum of 2n inputs and n outputs.
 The simplest encoder is a 2n-to-n binary encoder
 One of 2n inputs = 1
 Output is an n-bit binary number
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2n
inputs
n
outputs
Binary
encoder

6. Encoder – What is it?
 An encoder is a:
 Device
 Circuit
 Transducer
 Software Program
 Algorithm
 Person
 that converts information from one format to another

8. LINEAR ENCODER :
A linear encoder is a sensor,
with a scale that encodes
position. The sensor convert
the encoded position into
an Analog signal analog or
digital signa

20. The Digital Encoder
Digital Encoder more commonly called a Binary
Encoder takes ALL its data inputs one at a time
and then converts them into a single encoded
output.
So we can say that a binary encoder, is a multi-
input combinational logic circuit that converts
logic level "1" data at its inputs into an equivalent
binary code at its output.

21. 4-to-2 Bit Binary Encoder

22. The Digital Encoder
 Generally, digital encoders produce outputs
of 2-bit, 3-bit or 4-bit codes depending upon
the number of data input lines. An "n-bit"
binary encoder has 2n input lines and n-bit
output lines with common types that include
4-to-2, 8-to-3 and 16-to-4 line
configurations.

23. • 2n -to-n encoder : 2n inputs and n outputs.
• Input code : 1-out-of-2n.
• Output code : Binary Code
• Example : n=3, 8-to-3 encoder
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Inputs Outputs
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I0 I1 I2 I3 I4 I5 I6 I7 Y2 Y1 Y0
1 0 0 0 0 0 0 0 0 0 0
0 1 0 0 0 0 0 0 0 0 1
0 0 1 0 0 0 0 0 0 1 0
0 0 0 1 0 0 0 0 0 1 1
0 0 0 0 1 0 0 0 1 0 0
0 0 0 0 0 1 0 0 1 0 1
0 0 0 0 0 0 1 0 1 1 0
0 0 0 0 0 0 0 1 1 1 1
I1
I2
I3 Y1
Y2I4
I5
I6
I0
Y0
I7
Binary encoder
8-to-3 encoder Implementation

24. 8-to-3 Bit Priority Encoder

25. Digital Encoder using Logic
Gates
Q0=D1+D3+D5+D7
Q1=D2+D3+D6+D7
Q2=D4+D5+D6+D7
D0
D1
D2
D3
D4
D5
D6
D7
IMPUT
OUTPUT