Karnaugh map allows viewing the function in a picture form

1
Karnaugh map

• Karnaugh map allows viewing the function in a
  picture form
• Map is arranged such that two neighbors differ in
  only one variable
• It is easy to identify what terms can be combined
• Two terms must be adjacent in the map
• Example 1, 2, 3, and 4 variables maps are shown
  below

2
Adder truth tables, functions, and K-map
S ABCin ABCin ABCin ABCin Cout
BCin ACin AB
3
Farmers example truth tables and K-maps

• With three variables, we do not want X and Y or Y
  and Z to be equal (both 0 or both 1) at the same
  time
• With four variables, it is not a problem if W is
  also the same

F1 XY YZ XZ F2 XZWXYWYZW