Combinational Logic Circuit Design

Thread Starter


Joined Oct 11, 2011
Design a circuit that accepts a two-digit binary number as input and generates an output code equal to the square of that number.

I got the truth table I believe (correct me if im wrong) now I just dont know how to pull the circuit out of it:confused:

A B|x3 x2 x1 x0
0 0| 0 0 0 0
0 1| 0 0 0 1
1 0| 0 1 0 0
1 1|1 0 0 1


Joined Feb 24, 2006
Each column of the result is a boolean function of two variables.
Rich (BB code):
X3 = A & B
X2 = A & B'
X1 = 0
X0 = (A & B) | (A' & B)
Get the idea?

Thread Starter


Joined Oct 11, 2011
Got that part but would it be 3 seperate circuits? What do they all connect to? I'm just lost about that part. Do I karnaugh map them?


Joined Nov 25, 2009
In general, yes each output bit is a different Boolean function. You can find the function with a Karnaugh map, but Papabravo already did the job for you.

Now you need to design the logic gate connections from your inputs to produce the outputs.

Sketch a gate diagram and post it for us to comment upon.