Boolean Algebra, Logic Diagram, K-Map, Nor gates HELP

In summary, the conversation discussed implementing a function using Boolean Algebra and a K-map. The problem statement had 5 minterms and 4 don't cares, but the provided K-map had 6 minterms and 3 don't cares. After correcting the K-map, the solution was found to be F = (B'+D')(A+D')(A'+B'+C'), which cannot be represented using only two NOR gates.
  • #1
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Boolean Algebra, Logic Diagram, K-Map, Nor gates... HELP!

Homework Statement


F(A,B,C,D) = Sigma(2,4,6,10,12)
d(A,B,C,D) = Sigma(0,8,9,13) [Dont Care Functions]

Implement the function using no more than 2 NOR gates.

Homework Equations


K-map


The Attempt at a Solution


First of all, I am wondering if this is PHYSICALLY POSSIBLE.

Anyways, if you draw the K-map for it, you get
AB\CD
d 0 0 1
1 0 0 1
1 0 0 0
d d 1 1

As for the grouping, I grouped the Top 4 0s (0100, 1100, 0101, 1101), mid 4 0s (0101, 1101, 0111, 1111) and 2 0s on the right and middle (1011, 1111)

If you're doing Nor implementation.. it's usually easier to group the 0s so
F' = BD + A'D + ABC

(As for the notation, ' are inversion, + is or and * is And EG : AB is A and B)

But we want F.. so we apply the demorgan's theorem

F = (B'D')(AD')(A'B'C')

and that is our function.

I looked at this function and I thought there is no way to solve this problem only by using NOR gates.

Please help!
 
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  • #2
l46kok said:
F(A,B,C,D) = Sigma(2,4,6,10,12)
d(A,B,C,D) = Sigma(0,8,9,13) [Dont Care Functions]

AB\CD
d 0 0 1
1 0 0 1
1 0 0 0
d d 1 1

I think you got the table wrongly. There are 5 minterms in the problem statement but you have 6 in your table; and there should be 4 don't cares while you have only 3 in the table.
 
  • #3
l46kok said:
F' = BD + A'D + ABC

But we want F.. so we apply the demorgan's theorem
F = (B'D')(AD')(A'B'C')

and that is our function.

On a related note, De Morgan does not give you the transformation above. Read up on De Morgan again.
 
  • #4
l46kok said:

Homework Statement


F(A,B,C,D) = Sigma(2,4,6,10,12)
d(A,B,C,D) = Sigma(0,8,9,13) [Dont Care Functions]

Implement the function using no more than 2 NOR gates.

Homework Equations


K-map


The Attempt at a Solution


First of all, I am wondering if this is PHYSICALLY POSSIBLE.

Anyways, if you draw the K-map for it, you get
AB\CD
d 0 0 1
1 0 0 1
1 0 0 0
d d d 1

As for the grouping, I grouped the Top 4 0s (0100, 1100, 0101, 1101), mid 4 0s (0101, 1101, 0111, 1111) and 2 0s on the right and middle (1011, 1111)

If you're doing Nor implementation.. it's usually easier to group the 0s so
F' = BD + A'D + ABC

(As for the notation, ' are inversion, + is or and * is And EG : AB is A and B)

But we want F.. so we apply the demorgan's theorem

F = (B'D')(AD')(A'B'C')

and that is our function.

I looked at this function and I thought there is no way to solve this problem only by using NOR gates.

Please help!

Oops, I meant to put a d instead of that 1. It's fixed now.

And yeah, F is supposed to be

F = (B'+D')(A+D')(A'+B'+C')

But this still does not answer my question. It is utterly impossible to represent this just using two nor gates.
 
  • #5
l46kok said:
AB\CD
d 0 0 1
1 0 0 1
1 0 0 0
d d d 1

Oops, I meant to put a d instead of that 1. It's fixed now.

With this K-map, shouldn't there be only two groups of 0's?
 
  • #6
?

doodle said:
With this K-map, shouldn't there be only two groups of 0's?

? I can't see how you can have only two groupings of 0's and cover all 0's here.

Can you please explain how that might be done?
 
  • #7
?

doodle said:
With this K-map, shouldn't there be only two groups of 0's?

AH CRAP YOU'RE RIGHT

Now I can do it from here.

Thanks!
 

What is Boolean Algebra?

Boolean Algebra is a branch of mathematics and logic that deals with operations and rules for manipulating logical propositions. It is used to analyze and simplify complex logical expressions, which are represented using Boolean variables (usually denoted as true or false).

What is a Logic Diagram?

A Logic Diagram is a graphical representation of a logical expression using logic gates. It shows the logical relationship between different inputs and outputs, and helps in visualizing the logic of a circuit or system.

What is a K-Map?

A K-Map (Karnaugh Map) is a graphical method used for simplifying Boolean expressions. It is based on the concept of grouping and finding common terms in a truth table, which can then be used to simplify the logical expression.

What are NOR gates?

NOR gates (NOT OR gates) are one of the basic logic gates that perform logical negation. They output a true value only when all of their inputs are false. They are commonly used in digital circuits and are the opposite of OR gates.

How can I use Boolean Algebra, Logic Diagrams, K-Maps, and NOR gates?

Boolean Algebra, Logic Diagrams, K-Maps, and NOR gates are all important concepts in digital logic and circuit design. They are used to analyze, simplify, and design complex logical expressions and circuits. They are commonly used in fields such as computer science, electrical engineering, and mathematics.

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