Implement a function with 2-input NAND gates

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The discussion focuses on implementing a function using only 2-input NAND gates. The user has derived a function from a K-map but is struggling with constructing a multi-input OR gate using NAND gates. Participants suggest creating a tree structure of 2-input OR gates and emphasize the need to include inverters in each stage. The user reiterates the constraint of only using NAND gates, seeking clarification on how to proceed under this limitation. The conversation highlights the challenge of adapting traditional logic gate designs to fit the specific requirements of the exercise.
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Hello people!

I've just done a K-Map and gotten both the SOP and POS, but have a problem with this function:

f = acd + cab + dab + cdab + abcd ,
f = (a+b+c+d) * (b+c+d) * (b+c+d) * (a+b) * (a+c) * (a+d)

and got to implement it only using NAND gates with 2 inputs. Notice the underline is the negated variable.

Thank you so much in advance.
 
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alfonwob said:
Hello people!

I've just done a K-Map and gotten both the SOP and POS, but have a problem with this function:

f = acd + cab + dab + cdab + abcd ,
f = (a+b+c+d) * (b+c+d) * (b+c+d) * (a+b) * (a+c) * (a+d)

and got to implement it only using NAND gates with 2 inputs. Notice the underline is the negated variable.

Thank you so much in advance.

Welcome to the PF.

What did you get from your K-map? Do you know how to make an OR gate from NAND gates to implement your SOP solution?
 
Hi, thanks for your answer. I got (1 / 1 / 0 / 0 ... 0 / 1 / 0 / 0 ... 1 / 0 / 1 / 0 ... 0 / 1 / 0 / 0 ) I know how yo do an OR gate from 2 variables, not for more.

Image last number in right bottom is 0, not 1.
 

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alfonwob said:
Hi, thanks for your answer. I got (1 / 1 / 0 / 0 ... 0 / 1 / 0 / 0 ... 1 / 0 / 1 / 0 ... 0 / 1 / 0 / 0 ) I know how yo do an OR gate from 2 variables, not for more.

Image last number in right bottom is 0, not 1.

To build a wider OR gate, you just make a tree of 2-input OR gates...

http://www.electronics-tutorials.ws/logic/log11.gif
log11.gif
 
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berkeman said:
To build a wider OR gate, you just make a tree of 2-input OR gates...

http://www.electronics-tutorials.ws/logic/log11.gif
log11.gif

Thanks again for helping me.
Ok I understand the image you've attached but I have just to use NAND gates with 2 inputs.

I upload a picture where I show you the step I'm stuck in, just in the the part when I have to add both terms.
 

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You need to include the inverters as part of each OR stage. You show the final stage without those inversions...
 
But I only have NAND gates with 2 inputs. It's a rule from the exercise.
 
alfonwob said:
But I only have NAND gates with 2 inputs. It's a rule from the exercise.

You already show in that drawing how to use a 2-input NAND to make a NOT gate... That's how you got your first 2 NOR gate equivalents...
 

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