Page 194 - FUNDAMENTALS OF COMPUTER
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                   194                         Fundamentals of Computers                           NPP


                      Bubbled  AND and NOT Gates  can  be         ~~ëS> AND VWm NOT JoQ> H$mo NOR H$s ghm`Vm
                  replaced by NOR:                            go ~ZmZo na:

                                      A

                                      B
                                                                                     Y





                   3.18 Representation of Boolean Ex-          3.18 ~y{b`Z ì`§OH$ H$m à{V{Z{YËd
                   pression
                      Any  Boolean expression can be  repre-      {H$gr ^r ~y{b`Z ì`§OH$ H$mo Xmo àH$ma go {bIm
                  sented in two ways:                         Om gH$Vm h¡ …

                      1.  SOP (Sum Of Products) Form.             1. SOP  (g_ Am°\$ àmoS>ŠQ>)
                      2.  POS (Product Of Sum) Form.              2. POS (àmoS>ŠQ> Am°\$ g_)
                      Consider one by one.                        A~ h_ BÝh| EH$-EH$ H$aHo$ XoIVo h¢ …
                  1.  SOP Form:                               1. SOP  JwUZ\$bm| H$m `moJ
                      Consider the given expression:               {ZåZ ì`§OH$ H$mo XoImo…

                                                       F =  B . A  +  D . C
                      F is a Boolean function which is summa-     F EH$ Eogm ì`§OH$ h¡ Omo Xmo JwUZ\$bm|  .A B  VWm
                  tion of two products  A B .  and C.D. Other ex-  C.D H$m `moJ h¡Ÿ& Bgr àH$ma {ZåZ CXmhaU SOP H$mo
                  amples of SOP form are:                     Xem©Vo h¢…
                                               Y =     C . B . A  +  C . B . A  +  C . B . A

                                               Q =      D . C . B . A  +  D . C . B . A  +  D . C . B . A
                                               F =    Z . Y . X  +  Z . Y . X
                      A canonical SOP form is that in which all   EH$ Ho$Zmo{ZH$b SOP \$m°_© dh hmoVr h¡, {Og_| gmao
                  the products contain equal number of variables:  nXm| _| g_mZ g§»`m _| Ma  am{e`m± hmoVr  h¢Ÿ& O¡go,
                  e.g.  A  C . B .  +  C . B . A  +  C . B . A   is  canonical SOP  C . B . A  +  C . B . A  +  C . B . A   EH$ Ho$Zmo{ZH$b ê$n h¡ naÝVw
                  form. But the following expression is not:
                                                              {ZåZ Zht…

                            D . C . B . A  +  D . C . B . A  +  ABC . This is  called  D . C . B . A  +  D . C . B . A  +  ABC  `h  ñQ>¢§S>S>© \$m°_©
                  standard form.                              H$hcmVm h¡Ÿ&

                  2.  POS form                                2. POS (`moJm| H$m JwUZ\$b)
                      Consider the given expression:              {ZåZ ì`§OH$ Xo{I`o:
                                                    F =  (A +  B ) (A.  +  B )
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