Full subtractors

Table of contents

1. Introduction
2. Truth table
3. Circuit diagram
4. Full subtractor from universal gates

Introduction

The disadvantage of a half subtractor is overcome by full subtractor. The full subtractor is a combinational circuit with three inputs A, B, C and two output D and C’. A is the ‘minuend’, B is ‘subtrahend’, C is the ‘borrow’ produced by the previous stage, D is the difference output and C’ is the borrow output.

Truth table

Circuit diagram

Full subtractor from universal gates