1. Home
  2. Docs
  3. Digital Logic
  4. Combinational Logic
  5. Subtractor

Subtractor

A subtractor is a digital circuit that performs subtraction of binary numbers.

It’s a fundamental component in digital logic systems and is used to calculate the difference between two binary values.

Key components of a subtractor include:

Minuend: The number from which subtraction is performed.
Subtrahend: The number that is subtracted from the minuend.
Borrow (Borrow-in): A signal indicating whether a borrow needs to be taken into account in subtraction.
Difference: The result of the subtraction operation.
Borrow-out: A signal indicating whether a borrow occurred in the subtraction operation.

There are different types of subtractors, including half subtractors, full subtractors, and n-bit parallel subtractors.

Half Subractor:

A half subtractor is a digital circuit that performs subtraction of two single binary digits (bits).

It produces two outputs: a difference (D) and a borrow (B) output.

Unlike a full subtractor, a half subtractor doesn’t take into account any borrow from a previous stage, making it suitable for subtracting two individual bits.

Block Diagram:

image 52

Truth Table:

image 53

K-Map:

image 54

Logic Circuit:

image 55

Full Subtractor:

A full subtractor is a digital circuit that performs subtraction of three single binary digits: the minuend bit (A), the subtrahend bit (B), and a borrow-in bit (Bin) from a previous stage.

It produces two outputs: a difference (D) and a borrow-out (Bout) output.

Unlike a half subtractor, a full subtractor takes into account both the subtrahend and the potential borrow from the previous stage.

Block Diagram:

image 56

Truth Table:

image 57

K-Map:

image 58

Logic Circuit:

Full Subtractor

How can we help?

Leave a Reply

Your email address will not be published. Required fields are marked *