Implement a 1-bit adder.

Question

The truth table is:

A B Sum

0 0 0

0 1 1

1 0 1

1 1 0

So no carry. Is this correct?

Answer 1

If you have a XOR gate, everything is simple and you can simply calculate $Sum = A\oplus B$, where $\oplus$ denotes exclusive OR.

If you wish to implement $Sum$ with AND-OR logic / sum of products, find out all those product terms that gives $1$. In this case, only $A\overline B$ and $\overline AB$ gives $1$, and doing an OR operation over these two gives your $Sum$.

You can also try to implement $Sum$ with OR-AND logic / product of sums, by finding out all those terms that gives $0$.