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What Does A Circuit Board Do?

Have you ever opened up your electronics and seen those little green boards inside? They look complicated but it’s actually fairly easy to tell what their purpose is, once you know how. In this article, we’ll explain ways you can identify particular circuit boards and describe what exactly these boards do.

What Is A Circuit Board?

Simply put, a printed circuit board (or PCB) is just a small board that allows several different components to connect to one another. These are usually made of a semi-conductive material such as resin or fiberglass and are flexible enough to bend (within reason) without breaking.

There are some major benefits to using circuit boards: firstly, it ensures that thousands of these boards can be produced rapidly and economically. However, it also allows hardware to be as compact as possible, but it also prevents the need for every component to be connected by cables.

The image above shows a simple circuit. By using a circuit board, we can not only fix these individual parts in place but also ensure that the connections never fail. If one circuit track breaks, it’s a simple matter to create a new one around the fault.

Now, we know what you’re thinking: at least with cables, I could easily find a failing component. However, there are usually tell-tale signs with a PCB. The area around a troublesome part could be scorched, or the track electricity runs through will be broken. Now, how are circuit boards used?

Uses for Circuit Boards

Chances are if you’ve bought any electronics recently, they use circuit boards. Everything from your kettle to your TV uses them in order to function properly. Of course, the actual components that are connected differ from one device to another. Is there an easy way to tell what’s what?

Take a look at the image above. This is a Raspberry Pi 3, a single-board computer. By examining the tracks between components, we can see where electrical signals are sent. This allows us to hazard a guess at what each of the components is, assuming you know a little about how a computer operates.

For instance, look at the big black square in the center-left. Almost every component is connected to it in one way or another. From this, we can assume (correctly) that this black square is the system’s processor. Now, let’s assume something goes wrong – what can you do about it?

Repairing Damaged Circuit Boards

It’s necessary to remember that in most cases, you’re better off taking a damaged circuit board to a professional for repair. That said, if you have a soldering gun, you can fix most problems yourself with a little time.

Usually, if a circuit board is damaged, it’s one component at fault. You can use a multimeter to measure the electrical current in order to find the faulty part. From here, it’s a simple matter of removing it, and soldering a replacement in its place.


There’s no need to be intimated by circuit boards! Without them, the electronics industry wouldn’t have been able to keep up with our demands, so they’re extremely important. Hopefully, you now have a better understanding of what these crucial items are and how they work.

Now you know what a circuit board does. Did you ever think if it’s possible to charge your laptop without a charger? Yes, it is! Take time to read our guide, educate yourself on what are the possible ways to do it. Read it right here!

Justin Stuart

Justin is the head writer for My Tech Reviewer and he ensures that readers always get what they are looking for. He's a hard worker and spends more hours writing for My Tech Reviewer than he works at his part-time electrician job.