What is a PCB? A Beginner’s Guide

What is a PCB? A Beginner's Guide

Did you ever wonder how a smartphone can do so many things, yet be so small? That’s because of a modern invention known as the printed circuit board (PCB).

The typical smartphone has about 110 meters or about 360 feet of wire inside of it. Why? That’s what it takes to make the camera, speakers, display, Wi-Fi, antenna, battery, GPS, and more work together. 

That’s one football-length of wire running through a portable device you can easily hold in your hand. That’s the power of the printed circuit board (PCB), but what is a PCB? Sit tight as we explain. 

What Is a PCB

A printed circuit board or PCB is a multi-layered labyrinth of copper wires. It provides structure and organization for all of the components to be mounted on its surface. The copper wiring acts as a bridge that allows the components to communicate and work together. PCBs can come in a bunch of shapes, sizes, or designs. 

What’s Inside a PCB

To understand how a PCB works, we first have to understand the difference between a printed circuit board and its components, like microchips, resistors, capacitors, and connectors.

Components sit on top of a PCB but aren’t the PCB. Components of a circuit board are soldered or mounted on to the PCB. The term motherboard is a printed circuit board with the components already mounted to it.

A PCB is a flat board that does not have anything on it. Components like a smartphone aren’t mounted to a PCB but are attached to a PCB through sets of mating connectors and a flat cable.

If you look very closely at a PCB, you’ll see a ton of conductive wiring and a non-conductive insulator made from fiberglass and epoxy resin. From the side, you would see sandwich-like layers of copper wires, fiberglass, and epoxy resin all resting on top of one another.

A PCB usually consists of between 2 to 10 layers and can have as much as 50 layers. 

How Do Printed Circuit Boards Work

Inside the smartphone, attached to the PCB you would have the main chip, called the system on a chip or SOC for short. Its mounted on a grid of connection points called a ball grid array.

This connects the brain of the smartphone to other components like the GPS, camera, display, and other features of the phone through a series of wires. The series of wires are called traces, the more wires or traces in a set, the more data can be sent. Each trace is electrically separate from another. 

The PCB allows the system on a chip (SOC) to communicate with all the other components of the smartphone via hundreds of wires in precise order.

If you need printed circuit boards designed for your company, consider www.pcbnet.com. They offer same-day turnaround for prototyping and production within seven days. 

For Printed Circuit Boards Go With a Trusted Professional

PCBs are essential for a whole host of electronics. We hope this helps you answer the question: what is a PCB?

For more information on this topic and more, be sure to check our blog regularly.