what is pcb assembly

Everything You Need To Know About PCB Assembly l A Complete Guide

EVERYTHING YOU NEED TO KNOW ABOUT PCB ASSEMBLY L A COMPLETE GUIDE

Almost every electronic device or gadget has PCB as an integral part. This includes your laptop, smartphone, TV, microwave, washing machine and you name it. These devices can not function in absence of a PCB assembly. So, what is it actually and how it works? In this guide, we will discuss each and everything about PCB assembly. Keep reading!

WHAT IS PCB ASSEMBLY?

In simple terms, PCB assembly means assembling the necessary electrical components on a PCB or a pre-designed circuit board. On a large scale, it is done using special tools and machinery and this process is known as PCBA.

HOW PCBA IS DIFFERENT FROM PCB?

In general, PCB refers to a pre-designed circuit board which is empty. This means it doesn’t have any electronic components soldered on it. It looks like a plain green chip with a circuit design. PCB alone can not be used in a device until it is assembled.

On the other hand, PCB assembly is the combined process of soldering and assembling the necessary components on the empty circuit board or PCB. The finished PCBA is then used in various electronic devices and gadgets.

WHAT ARE THE PARTS USED IN PCB ASSEMBLY?

PCB assembly involves a number of steps. However, the number of steps is not fixed. It is a non-linear process in which many considerations have to be taken such as the type of circuit, type of device or components etc.

Below are the most common components and parts used in a PCB assembly :

* A pre-designed PCB or an empty circuit board
* Necessary components that need to be soldered on the given circuit board. This varies from device to device and the complexity of the circuit. For instance, the components used for a radio will be less as compared to the components needed by a TV.
* Soldering items such as solder wire, paste, solder bar and performs. The preforms again vary according to the type of soldering.
* Other equipment for soldering such as a soldering machine, soldering station, testing equipment etc. Again, the equipment depends on the type of assembly, cost and desired outcomes.
* Soldering flux

So, these are the basic components that are needed for a PCB assembly. Note that these are not the final materials and can be more or less depending upon the type of assembly and the expected outcome. Once all the components are gathered, the assembly process can be started.

TYPES OF PCB ASSEMBLY

A PCB can be assembled using several mounting methodologies. These are known as mounting technologies for circuit board assemblies. The selection of mounting technology depends upon certain factors such as cost, application, scale etc. The most common types of PCB mounting technologies are mentioned below :

SURFACE MOUNT ASSEMBLY

The Surface Mounting Technology or an SMT is a process in which the electronic components etched on the PCB are directly soldered on the surface of the circuit board. The resulting circuit board in this process is known as a surface mount device or simply an SMD. Initially, this mounting methodology was known as “planar mounting” but later came to be known as SMT.

This is the most common PCB assembly method that is used by a majority of electronic components. It is widely used to such an extent that it has almost replaced the through-hole mounting technology. The main reasons behind the success of this method are its ability to work on the smaller circuit boards and the increased circuit densities.

In general, Surface mount assembly uses a soldering method to join the component directly on the board.

THE THROUGH HOLE ASSEMBLY

The through-hole technology is a mounting process in which the electronic components are first inserted through the holes drilled on a plate and then joined using soldering. Moreover, soldering can be done manually or by using special soldering tools.

The through-hole mounting technology is the traditional process and has been replaced greatly by the modern surface mounting methodology.

But before the arrival of modern scolding technologies, it was popularly used for multi-player and complex circuit boards. It was used for joining the electronic components with the power conductive layers so that the circuit board functions properly.

The components are connected with the wire leads that are used for connecting the other side of the through-hole plates.

It is different from the surface-mount technology due to the fact that it offers increased cohesion to the PCB components because the units are joined on the circuit board itself.

ELECTRO-MECHANICAL ASSEMBLY

This PCB assembly technology is used on a large scale and covers a broad category of functions like power generation, mechanical processes etc.

The electro-mechanical mounting technology is used for the complex circuit boards that need a lot of wiring and components. Also, due to these complexities, PCBs are assembled manually which can be very time-consuming sometimes.

However, most of the manufacturers divide the entire assembly process into segments and assign each segment to a specialist. Hence, they save a lot of time and cost of manufacturing. But, from a customer’s point of view, they are still a bit costly.

SOME COMMON USES FOR EACH TYPE OF PCB ASSEMBLY

As we already discussed, Surface mounted methodology is widely used for a number of devices. It has a wide range of applications, consumers and users in the electronics department. It is used in computers, microwaves, TV, washing machines, radios, smartphones, dishwashers and whatnot.

Through-hole technology as we discussed was used before the arrival of SMT. It was used mainly for complex computer circuits.

Finally, the electro-mechanical PCB assembly is used for power generations, power distributions, control systems and other heavy areas due to its enhanced electrical and mechanical functions.

CONCLUSION

As you can see, PCB assembly is the most integral part of our day to day lives. The mounting methodologies or the technologies of PCBA have changed a lot over the years. Each assembly has its own set of pros and cons and is equally important for their specific areas.