NAND circuit to NOR

Thread Starter

nanduko

Joined Oct 31, 2009
11
Hello everyone !

So i have to turn this circuit that is made of nand gates into the equivalent of this but this time only with NOR gates. This is the circuit :




First i tryed to turn the circuit into some boolen algebra statement but nothing happned, actually it became harder =/ i am strungling trying to solve this loads hours ....help me please...
 

Thread Starter

nanduko

Joined Oct 31, 2009
11
Take a look at DeMorgan's Theorem.

hgmjr
Well ok De morgan's theorem, but i need an expression 1st for the circuit, there is where i am strungling , i am getting confused all the time....

This is stupid but anyway... my conclusion is: (((((pp)'p)')'(rr)')')'

this is not right, right?
 

hgmjr

Joined Jan 28, 2005
9,027
Well ok De morgan's theorem, but i need an expression 1st for the circuit, there is where i am strungling , i am getting confused all the time....

This is stupid but anyway... my conclusion is: (((((pp)'p)')'(rr)')')'

this is not right, right?
First observation is that there is no q in your boolean expression.

Have you noticed that four of the nand gates are configured as simple inverters?

hgmjr
 

Thread Starter

nanduko

Joined Oct 31, 2009
11
First observation is that there is no q in your boolean expression.

Have you noticed that four of the nand gates are configured as simple inverters?

hgmjr
indeed theres no q, it was meant to be like this (((((pp)'q)')'(rr)')')'

but still not sure if this is .
 

hgmjr

Joined Jan 28, 2005
9,027
HINT: If you feed the same signal into both inputs of a NAND gate, all that is doing is inverting the input.

hgmjr
 

Thread Starter

nanduko

Joined Oct 31, 2009
11
hmmmm i tried to simplify it a bit, not sure again if its right

( (p' NAND q)' NAND (r') )' =

((p' q) nand (r') )' =

(((p' q) (r') )' )' =

((p+q') + r)' =

(p'q) r'

i believe theres a mistake somewhere
 

hgmjr

Joined Jan 28, 2005
9,027
If you take a look at post #8 in this thread, you will see that I got the same simplified answer you have in post #11.

I guess your next step is to implement this boolean expression using NOR gates. Right?

hgmjr
 

Thread Starter

nanduko

Joined Oct 31, 2009
11
If you take a look at post #8 in this thread, you will see that I got the same simplified answer you have in post #11.

I guess your next step is to implement this boolean expression using NOR gates. Right?

hgmjr
yeah as long as this result is ok for the given circuit, ah btw forgot to mention that i hd already proved that p'q = p nor (p nor q) , the problem is the r' now, should i call for example p'q=d and say r'd = r nor ( r nor d) ?

Thanks in adance
 

hgmjr

Joined Jan 28, 2005
9,027
My thought was that if you needed an inversion, you would feed the same signal into both inputs of a NOR gate just as was done in the NAND gate version of the circuit.

hgmjr
 

Thread Starter

nanduko

Joined Oct 31, 2009
11
My thought was that if you needed an inversion, you would feed the same signal into both inputs of a NOR gate just as was done in the NAND gate version of the circuit.

hgmjr

indeed i could feed a nor gate with 2x r so the result is r' , but still theres a multiply , how can do that as a nor gate . i mean --> (p'q) multiply r'
 

hgmjr

Joined Jan 28, 2005
9,027
You do realize that there is not an actual multiply operation involved. That is simply the indication of an AND function.

hgmjr
 

Thread Starter

nanduko

Joined Oct 31, 2009
11
nor version of this (p'q) r' is :





hopefully

EDIT: i think that the second NOR (where r entrance is ) is not needed tho.
 
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