Next: N-bit adder
Up: Combinatorial Logic: Binary AdderNovember
Previous: Full Adder
- Now, we can combine the half adder and the full adder to construct a 2-bit adder.
- The least significant bit does not require a full adder as there is no
- The half adder determines the least significant bit of the sum as the XOR
of the least significant bits of the inputs.
- The carry output of the half adder becomes the carry input of the full
- The full adder computes the sum of the inputs A1 and A2 and the
- Example: A=3 (11) and B=1 (01):
- Result: 100, which is the binary representation of 4.
Prof. Bernd-Peter Paris