Page 80 - Computer science 868 Class 12
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The truth table of a Binary to Decimal encoder having input lines A , A , A  and A  and 10 outputs represented by AND
                                                                               2
                                                                                      3
                                                                         0
                                                                            1
              gates D  to D  is shown below.
                     0
                          9
                 A 3     A 2    A 1    A 0     D 0    D 1     D 2    D 3     D 4    D 5     D 6    D 7     D 8    D 9
                  0      0      0       0      1       0      0       0      0       0      0       0      0      0
                  0      0      0       1      0       1      0       0      0       0      0       0      0      0
                  0      0      1       0      0       0      1       0      0       0      0       0      0      0
                  0      0      1       1      0       0      0       1      0       0      0       0      0      0
                  0      1      0       0      0       0      0       0      1       0      0       0      0      0
                  0      1      0       1      0       0      0       0      0       1      0       0      0      0
                  0      1      1       0      0       0      0       0      0       0      1       0      0      0
                  0      1      1       1      0       0      0       0      0       0      0       1      0      0
                  1      0      0       0      0       0      0       0      0       0      0       0      1      0
                  1      0      0       1      0       0      0       0      0       0      0       0      0      1
              The following is the logic circuit diagram of a Binary to Decimal Encoder:

                                               A 3    A 2     A 1    A 0



                                                                                    D 0


                                                                                    D 1


                                                                                    D 2


                                                                                    D 3


                                                                                    D 4


                                                                                    D 5


                                                                                    D 6


                                                                                    D 7

                                                                                    D 8


                                                                                    D 9



              Working Principle of Binary to Decimal Decoder:
              If we take A  = 1, A  = 0  A  = 0 and A  = 1 as input the output across the eight gates are as follows:
                                               0
                         3
                               2
                                     1
              D  = A '.A '.A '.A '    is 0
                       2
                    3
                0
                         1
                            0
              D  = A '.A '.A '.A     is 0
                1
                            0
                         1
                    3
                       2
                7878  Touchpad Computer Science-XII
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