What is PCB (printed circuit board) and how it's made

The PCB board is the fundamental component of the electronic industry and electronic projects. Each device and gadget is made on board. Older electronic components and devices are made and connected with point-to-point construction. That needed a larger number of wires and components connected. This larger number of wire make complications and difficult to make circuits and in some cases damage the devices.

However, the use of a PCB board for the creation of different projects and devices helps to easily connect components of the board and proper design of the circuit. This simple and easy configuration of components helps the circuit board to be used in each electronic device. So let get started with What is PCB (printed circuit board) and how it’s made.

What is PCB Board

The PCB board is also known as a printed wiring board that is used to make connections between components in circuits. it is a laminated sandwich structure for an insulating layer and is a conducive layer, on board every conducive layer is made in a certain configuration of traces, and planes. Electrical components can be configured on the conductive pad at the external layer with the use of soldering.

PCB board comes in different types such as single layer double, multilayer, etc. In the multilayer boards layers connected through vias, plated through holes. PCB boards are used in different electronic products.

Different Layers of PCBs

There are main four types of layers that are configured in each type of printed circuit board.

Substrate layer

This layer is made with fiberglass that provides the rigidness to board. Substrate layers can also created with ue of epoxies but they not are as durable as fiberglass.

Copper layer

The copper layer of PCs is created with the use of a thin layer of copper foil. The single-sided board comes with one conducive material layer on a single side. That means for single-sided board one side is used to make component connections. The double-sided board has two-sided conductive layers which means both sides are used for component connections to make circuits. The copper layer thickness is defined based on the power handled by the board. Board that needed to handle high power needed thick copper

Solder mask layer

Over the copper layer, there is a solder mask layer applied that is green colored. it insults copper and makes sure that it does not make connections with other layers and components.

Silkscreen layer

Silkscreen layers come with different symbols and component details and help to easy circuit creation on board. Silkscreen is normally white colored but it is also used in red, grey, and black colors. With using single colors different color combinations are also used.

Different Types of PCB

Single sided PCB

The single-sided board comes with one layer of conductive layer at the single side of the board. another side of the board used for the component connection. These boards are made with the use of a substrate layer, a conductive layer, a solder mask, and a silkscreen layer applied at last. These boards are very commonly used in projects and devices since they are easy to make and have less cost manufacturing involved. With using simple circuits also used in printers and vending machines

Double-sided PCB

These boards also called two-layer boards help to make complicated circuits and designs. Contrary to single-sided boards, double-layer boards have conductive layers on two sides. There are two common methods used to connect components on both sides of the board through-hole and SMT technology. It also has the same layers like copper, substrate, solder mask, and silkscreen but on both sides. Their easy use and flexible features make them common for different uses. it used in complicated circuits like lighting systems

Multi-layer PCB

Multilayer boards have more than two layers. The double-sided board has two conductive layers on top and bottom at the substrate. While multilayer board comes with a minimum of three conductive layers of conductive materials. All layers of these boards are connected with the use of copper-plated holes. Multilayer boards can have 4, to 40 layers according to the need of the project. The multilayer board comes with a complicated design.

The upper and lower layers of these boards are like double-sided boards but stacked layers on both sides of the core. All layers are compressed to make a single multilayer board. Components used to make circuits are assembled on both sides of boards. All internal layers are stacked layers for routng. On any side of the board, SMT and through-hole components can be connected. For SMD component connection SMT technique used

Rigid PCB

These boards have a rigid structure and are made with the use of different layers that are connected with the use of adhesive. Based on the project needed rigid boards can be made in single layers double layers and multiple layers. Rigid boards are less costly and can be made in larger quantities. Their rigid nature makes them useful for industries since they are easy to handle heavy components without any damage.

Flexible PCB

Flexible boards also called flex PCBs or flex circuits made for accurate fitting of any device. So these boards are thin, less weight, and can work well in small spaces. These boards do not use fiberglass as a substrate which is a rigid material but use Kapton as a substrate. These boards are famous since they do not need high space to make boards they handle high temperatures and support different components and connectors. Their main feature is to easily handle product

Rigid-flex PCB

The rigid-flex board comes with rigid materials with a combination of flexible materials connected with flexible adhesive material. The rigid part provides the mechanical strength to component connect and the flexible part helps to make accurate shapes. The rigid part of the board is made with Fr4 and the flexible part is made with polyimide. The layers are bonded with the use of adhesion methods. Conductive traces are etched on rigid and flexible layers. Vias and component holes are plated through flexible and rigid layers helps to interconnections.

HDI PCB

HDI boards also called high-density interconnect boards are new types of boards. But they are now growing fast in the PCB industry. HDI boards come with higher circuit density than conventional boards. With that, these boars also have blind, and buried vias with micro vias in small dia. It helps to connect small-size components on boards to help the high-speed signal transm

HDI PCBs have higher circuitry density compared to more traditional circuit boards. Plus, HDI PCBs also have blind and buried vias, alongside micro vias, which have a smaller diameter. This means that designers are also able to place smaller components closer together on the board, resulting in the quicker transmission of signals and less signal loss or crossing delays.

For these reasons, HDI PCBs are compact and have fewer layers than multi-layer PCBs. However, what HDI PCBs lack in size, they more than makeup for in quality. Due to this, they’re popular in advanced technology systems such as smartphones and game consoles.

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