What is a PCB?

  PCB is a non-conductive and multi-layer copper printed circuit board, where all electrical and electronic parts are connected to each other through a common board and by means of a physical support installed on the bottom of the board.

Before the growth and expansion of PCB, circuits were made by point-to-point wiring, which increased complexity and uncertainty in the circuit. As a result, we were never able to build a large circuit like a motherboard (by connecting parts with wires). In PCB, all parts are connected without wires and from the inside, which leads to reducing the complexity of the overall circuit design. The PCB design method is such that it has a special application in providing electricity and connection between circuit parts.

PCBs can be designed according to the specifications required by the user, and this (optional and diverse design) can be found in many electronic devices, including televisions, mobile phones, digital cameras, and computer components such as graphics cards, motherboards, etc.

PCB is used in many other fields including medical equipment, industrial machinery, automotive and lighting industries.

Types of PCB boards

There are several different types of PCB for a circuit. We should choose the right type of PCB among these types according to our needs.

•Monolayers

• double layer

•multilayer

• flexible

• Solid-hard

• Flexible-hard

Single layer PCB

Single-layer PCB, which is also called one-sided, is simpler than other PCBs, and for this reason, it is the most widely used type of PCB in designing and manufacturing. One side of this PCB is covered with a layer of conductive material. In general, copper is used as a conductive material for this PCB due to its high conductivity.

 A soldered layer is used to protect the PCB from oxidation and a silk insulating layer that defines the placement of all the parts.

In this type of PCB, only one side of the PCB is used to connect various types of electrical and electronic components, such as resistors, capacitors, inductors, etc. And all these parts are soldered on the board.

 These types of PCBs have a reasonable price, and for this reason, they are used in the circuit of calculators, radios, printers and solid state drives.

Double layer PCB

This type of PCB is also known as Doro. In this type of PCB, a conductive plate is glued on one side of the board and a conductive layer on the other side.

Communication between two conductor layers is established using holes called via. As shown in Figure 2b, these pads are electrically connected to each other through a hole inside the board. Among the advantages of this type of PCB, it can be mentioned that it can be changed and more flexible and its relatively low cost

But the most important advantage of this type of PCB is reducing the size of the board because it makes the circuit more compact. This type of PCB is mainly used in industrial controls, converters, UPS systems, HVAC applications, telephones, amplifiers and electrical monitoring systems.

Multi-layer PCB

This type of PCB has at least three copper conductor layers. For added safety and strength, layers of electrical insulation are bonded over an insulating core at high temperature and under pressure to ensure that excess heat does not damage any part of the circuit. The design of this type of PCB is very complex, and for this reason, it is used in large and very complex electrical works that have very little space and a compact circuit. PCB type is used in large applications such as GPS technology, satellite system, medical equipment, file server and data storage.

Flexible PCB

This type of PCB is also known as switchable circuit. In this type of PCB, flexible plastic materials such as polyamide, peak (polyether ether ketone) or a layer of transparent conductive polyester are used. This type of PCB is very complex and includes different ranges of layers such as single-layer switchable circuit, two-layer switchable circuit and multi-layer switchable circuit. The switchable circuit is used in the manufacture of organic light-emitting diodes, LCD manufacturing, switchable solar cells, automotive industry, door-to-door telephones, cameras and complex electronic devices such as laptops.

Solid and hard PCB

These types of PCBs are made of solid materials. Like flexible PCBs, they have different layers. The shape of this type of PCB does not change after design and manufacture, and it cannot be bent, and this is the reason why this type of PCB is known as solid and hard. The lifespan of this type of PCB is very long, and for this reason, it is used in the construction of various parts of the computer such as ram, gpu and cpu. The most widely used type of this PCB is the one-sided solid type, which has the most production and has a simpler design than the others.

 Multilayer solid PCB can also be made more compact by adding layers to 9-10 layers.

Changeable solid PCB

The combination of changeable circuit and hard and solid circuit makes the most important board. Solid-state switchable boards consist of multiple switchable layers glued onto a number of solid-state PCB layers. The switchable solid board is shown in the figure below. This type of PCB is used in making cell phones, digital cameras, cars, etc.