Understanding Printed Circuit Boards (PCB’s)

Every time we take our Mobile Phones, Tablets, Laptops we don’t think much about the circuit and the components from which it is made, whether it is the Microcontrollers, the SoC’s, power unit, Cameras, the touchscreen and much more. However, the question comes how do these components are connected? How do they communicate with each other? To answer these questions there must be some conducting surface or wires through which these are connected. Here comes the work of Printed Circuit Board (PCB’s). Anyone who has ever opened up a piece of electronic equipment has seen a printed circuit board, also known as a PCB. They are thin, flat, and often green rectangular substrates that are covered with a maze of fine copper lines and silver pads and are the heart and soul of most electronic equipment.

What are PCBs?

To answer this question let us first see the classical definition –

Hardwiring of PCB

But why use PCB, since we can use wires –

But, you might wonder why don’t we connect the components directly through wires like every other device that we use to connect. Before the advent of the PCB, circuits were constructed through a laborious process of point-to-point wiring. This led to frequent failures at wire junctions and short circuits when wire insulation began to age and crack. A significant advance was the development of wire wrapping, where a small gauge wire is literally wrapped around a post at each connection point, creating a gas-tight connection, which is highly durable and easily changeable.

What PCB’s are made up of?

The PCBs are used in various devices from a small watch to big computers. To provide a sturdy and stable surface to mount all the components as well as to provide suitable circuit tracks for conductivity, the PCBs must be both conductive as well as insulated in specific sections designed by the Engineers. Today, boards are made to be larger and smaller than this standard, but the standard probably remains the most common thickness for designs. It is more accurate to say there is a range of common or standard PCB thicknesses. These include 0.031in (0.78mm ), 0.062in (1.57mm) and 0.093in (2.36mm).

What are the types of PCBs?

Depending on the application of use, PCBs are broadly classified as follows –

What is in our smartphones?

When we talk about Mobile phones be it a Google Pixel or an iPhone there is a big competition in terms of size, thickness, and weight of the phone. Every smartphone manufacturer wants lightweight circuitry that can perform the functions well as it fits the small and compact body of the phone.


1. https://www.pcbcart.com/pcb-capability/layer-stackup.html#:~:text=Multilayer%20boards%20usually%20consist%20of,0.1mm%20to%200.3mm.

An enthusiastic and ambitious Electronics Engineer. Freelance Content Writer and Graphic Designer.