Page 43 - CITS - Electronic Mechanic - TT - 2024
P. 43

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
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