Page 61 - computer science (868) class 11
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A'                A'.B'.C
                                  B'
                                  C




                                  A'               A'.B.C'                     A'.B'.C + A'.B.C' + A.B'.C' + A.B.C
                                  B
                                  C'



                                  A                  A.B'.C'
                                  B'
                                  C'


                                   A                 A.B.C
                                   B
                                  C

                 Applications of the XOR gate:

                 •  Used in half and full adders.
                 •  Used in pseudo-random number generation.
                 2.7.7 XNOR Gate
                 The XNOR gate is a digital logical gate that produces 0 (low) as output for an odd number of 1 (high) as input. It
                 is pronounced as exclusive NOR gate. It is the complement of the XOR gate. An encircled dot sign ⊙ is used to
                 show the XNOR operation.
                 The symbol and truth table of the XNOR gate are given below.


                                      A          B          A⊙B
                                                                           A                  A⊙B
                                      0          0           1
                                                                           B
                                      0          1           0
                                                                              Symbol of XNOR gate
                                      1          0           0
                                      1          1           1          The Boolean expression of the two
                                                                        variable XNOR gate is A'.B' + A.B.
                                 Truth table of two variables XNOR gate

                 The logic circuit diagram of the two variables XNOR gate is as follows:


                                                  A               A.B
                                                  B

                                                                                 A'.B' + A.B


                                                 A'               A'.B'

                                                 B'









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