How does a breadboard work?

The breadboard is a key part of every MakeCrate project. Let’s take a look at why we use them, why they are called breadboards, and how they work.

Why use a breadboard?

The type of breadboards we use are called solderless breadboards. Soldering is a process that connects two pieces of metal by putting a filler metal – called solder- in the joint and melting it. It takes some skill to do, and it makes the items you’ve connected stay together permanently. Because we want to be able to experiment and reuse our components, and because good soldering takes some skill, we use a breadboard to build a prototype– a working circuit that we can easily change around or take apart.

Why is it called a breadboard?

Early radio circuits were made from bare copper wires tacked to wooden boards- sometimes the same boards that were used from slicing bread! While the technology has evolved, the name stuck.

How does it work?
By now you may have seen that if you don’t line things up exactly right on the breadboard, your circuits won’t work properly. Let’s take a look at what is going on inside the board to understand why that happens.

The central part of the breadboard consists of a lot of small rows of metal called terminal strips. These correspond to the numbered rows on the front of the breadboard.

Each terminal strip contains a small clip that holds any wires or component legs inserted into it.

Because the metal clip is conductive, the strips allow current to flow to any component contained in the clip. Because the plastic around the clip is an insulator, the electricity cannot flow to any component contained outside the clip (See our article on LEDs for a review of conductors and insulators.)

You can see that the breadboard has two long rows of metal running the length of the board. These are called the power rails of the board. These allow us to provide power to the entire board, since we may need to power a number of components in a number of different terminal strips. By connecting the power rails to power or ground, and then connecting the terminal strips to the power rails, we can power each row separately.

For a more in-depth look at breadboards, check out this article.