1.4.3 Boolean Logic 4: Half & Full Adders

In this lesson, we will learn about half adders and full adders, which are fundamental building blocks in digital circuits for performing binary addition. We will explore their functionality & truth tables.

Learning Objectives:

  • Understand the operation of half adders and full adders.
  • Analyse the truth tables for half adders and full adders.
  • Explore the differences between half adders and full adders.
  • Learn how to combine multiple adders to create more complex circuits.

A half adder is a digital circuit that performs the addition of two single-bit binary numbers. It has two inputs, typically denoted as A and B, and two outputs: the sum (S) and the carry (C). The truth table for a half adder is as follows:

  • Inputs: A, B
  • Outputs: Sum (S), Carry (C)
  • Truth Table:
    A B Sum (S) Carry (C)
    0 0 0 0
    0 1 1 0
    1 0 1 0
    1 1 0 1
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