i need to build a comparator
of 2 numbers (each number has two bits)

i think that we should subtruct them
and if the last bit (sign bit) equals to one then the top number is smaller

but here i get a totaly different solution
i cant unerstand it:

http://s290.photobucket.com/albums/ll279/t...nt=IMG_8812.jpg

 

The conditions a comparitor has to output are greater than, equal to, or less than. If you let one value be A and the other B, then you device has to have one output true for A compared to B.

 

so i need to decide that by the least digit of their subtraction?????????

cause i need to build it using "full subtractor " components

and i cant understand the circuit of the solution
which i presented in the first thread

 

I have to build a 8-bit comparator too using 4 bit comparator...
what is the number of your IC??

 

466921864 my icq

 

Transgalactic,

Doghar is asking for the type of chip you have, the number printed on the IC package.

 

no
i am solving theoretical questions