How To Implement This Function With 2 Input Nand

  • Thread starter Thread starter transgalactic
  • Start date Start date
  • Tags Tags
    Function Input
Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
2 replies · 5K views
transgalactic
Messages
1,386
Reaction score
0
Default How To Implement This Function With 2 Input Nand..
(+) =XOR

F(w,x,y,z)=(w'+x'+y')(+)xyz

i tried to :

F(w,x,y,z)=(w'+x'+y')(+)xyz=(w'+x'+y')' *(xyz) + (w'+x'+y')(xyz)'=
=(wxy)(xyz)+(w'+x'+y')(x'+y'+z')
..
..
in the end i get
=wxyz+w'x'+w'y'+w'z'+x'+x'y'+x'y'+y'+y'z'+y'z'

what to do know?
how to transform implement it with a two input line NANDs
?
 
Physics news on Phys.org
Well, the word NAND should scream Sum of Products (SOP), so try to get your function to that point, then you can modify it further. After playing around with your function, you should get something like:

[tex]F = \overline{x} + \overline{y} + (\overline{w})(\overline{z}) + wxyz[/tex]

(Keep in mind that [tex]A+AB = A[/tex]; your final equation doesn't take that into account).

I'm going to show you another useful proof:

[tex]\overline{ABCD} = \overline{A}+\overline{B}+\overline{C}+\overline{D} = (\overline{A}+\overline{B})+(\overline{C}+\overline{D}) = \overline{AB}+\overline{CD} = \overline{(\overline{AB})(\overline{CD})}[/tex]

The function is also equal to (through DeMorgan):
[tex]F = \overline{xy ( \overline{ \bar{w} \bar{z} })( \overline{wxyz}) }[/tex]

Use the proof above on that form of F. Use the proof above to get [tex]\overline{(wxyz)}[/tex], too. Use NANDs as inverters to get w' and z'.
 
I think There is a mistake it should be [tex]\overline{AB}+\overline{CD} = \overline{({AB})({CD})}[/tex]