Digital Logic
Half Adder
A combinational circuit that adds two single bits, producing a sum and carry output but no carry input.
Detailed Explanation
The half adder is the simplest adder—Sum = A XOR B, Carry = A AND B. It cannot chain directly because it lacks a carry input. Two half adders plus an OR gate form a full adder.
Half adders are useful for incrementers (adding 1) and as building blocks in more complex arithmetic circuits.