Beginner Combinational Circuits 7 コンポーネント
Half Subtractor
Subtracts one bit from another, producing a Difference bit and a Borrow bit. The complement of the half adder.
学べること
- Derive Difference and Borrow from a truth table
- Contrast the half subtractor with the half adder
- Identify when a borrow is generated
仕組み
The Difference output is A XOR B; the Borrow output is high only when A=0 and B=1 (you can't take 1 from 0 without borrowing). It is the subtraction counterpart of the half adder.
使用コンポーネント
実世界での応用
The least-significant stage of any subtractor, and a building block for ALUs and calculators.