Half Adder: A brief introduction and its implementation in reallife context.

About me

Hello, I am Antonio Pedro, I am a first year student of Computer Science and Engineering at IIITD. I am a I.T enthusistic since I was in secondary school and at this moment I am working as Mobile Developer for at least 3 years ago. I finished my middle grade school in Information and Technology at Instituto Médio Politécnico dos Dembos.

Introduction

In this article I am going to show you the implementation of Half Adder.

The addition of two bits is perfomed using the concept called Half Adder(HA). It is already known that in addiction we have augent and addend the bit. The augend and the addend are goint to be our input variables. By the way, for output we must have a Sum and a Carry. See the figure bellow:

Source: https://media.geeksforgeeks.org/

It is clear now that we have two inputs and two outputs.

Note that in half adder we have to get only two inputs, more that this we will had talking about FULL ADDER.

before going on with the explanation, let’s see an example of a binary addition.

Exemple of addiction.

Truth Table

I have noted before that in hald adder we have only two inputs, then we are going to have 4 possibles combination for out truth table.

Truth Table of Half Adder(source: https://media.geeksforgeeks.org/)

To understand this table, you have to note that:

0 + 0 = 0, and Carry = 0

0 + 1 = 1, and Carry = 0

1 + 0 = 1, and Carry = 0

1 + 1 = 0, and Carry = 1

The get the boolean function we should use K-Map, but by convection we can note that:

Sum = A’.B + A.’B = A XOR B

Carry = A.B

And know we can draw our circuit diagram.

Source: https://media.geeksforgeeks.org/

Note that: We have a XOR gate in combination with AND gate. XOR gate is for Sum and AND gate is for Carry.

Implementation:

Now I am going to show and share with you the implementation of half design in reallife context, using a breadbord, LEDs(one-red for Sum, and other yellow for Carry output), SupplyPower, Resistors, Slideswitches(one for A input and other for B input), and the most important two ICs, XOR(for Sum) and AND(for Carry).

Experiment 1. (A= 0, B= 0, see the tuth Table to see the outputs)

Experiment 2. (A= 0, B=1, see the truth table to see the outputs)

Experiment 3. (A= 1, B=0, see the truth table to see the outputs)

Experiment 3. (A= 1, B=1 see the truth table to see the outputs)

Now we are done, you can check this project on TinkerCad(I am going to give it in Bibliography section).

Please: Don’t make any alteration of this. Instead, you can only make simulations.

Sumary

In this article you learnt:

1 — What is half adder (its truth table, circuit diagram)

2 — Implementation of Half adder in realife context using a breadboard and other components.

Bibliography and Links

Half Adder in Digital Logic, on GeekForGeeks, https://www.geeksforgeeks.org/half-adder-in-digital-logic/

TinkerCad project — Half Adder by António Pedro,

Tinkercad | From mind to design in minutes

Again, please Don not make any alteration!

Thank you for reading this, if you think it was helpful, please share it and give it claps! And don’t forget to comment if you have any doubt!

Bye.