Page 43 - CITS - Electronic Mechanic - TT - 2024

ELECTRONICS MECHANIC - CITS

Boolean expression
Y1 = D3+D2
Y0 = D3 + D2’D1
• Circuit diagram of Priority Encoder

Octal to Binary (8 to 3) Encoder
Truth table of octal to binary encoder

Input Output

D 0 D 1 D 2 D 3 D 4 D 5 D 6 D 7 Q 2 Q 1 Q 0
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

• It has 8 input lines & 3 output lines.
• Corresponding to the eight input octal numbers we get three bit binaryoutput.
• In encoders only one input will have a one value at any given time.

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CITS : E & H - Electronics Mechanic - Lesson 9 - 29