The most commonly used mounting styles for PCB assembly are surface mount technology and through hole mounting. Each style has their own advantages and disadvantages. Likewise, manufacturers have different reasons for preferring one style over the other.
For the benefit of consumers, it is recommended that you learn more about the two mounting styles even if you will not be taking on the task of making your own printed circuit boards. After all, PCBs can be found in many of the electronic devices that you most likely use on a daily basis. Therefore, it is in your best interest to learn about what goes on behind the scenes regarding the creation of your printed circuit boards.
The first mounting style that you should familiarize yourself with is through-hole mounting. Its name is derived from the process of passing the lead wires of various individual components through different holes. After all leads have been passed through their specific holes, they are then soldered in place. This mounting style is commonly utilized in assembling multilayer printed circuit boards.
The second mounting style that is most commonly used by manufacturers for PCB assembly is surface mount technology. Although this type of mounting style is fairly recent when compared to through-hole mounting, its efficiency has allowed it to quickly gain a large following in a short amount of time.
Instead of using holes to mount wire leads, this method makes it possible to directly solder the leads onto the surface of the printed circuit boards. As a result, despite an increase in the number of components that need to be placed on printed circuit boards, surface mount technology has made it possible to create PCBs that are lighter and more compact than their predecessors.
Aside from the varying processes involved for each mounting style, there are still other ways in which they contrast with one another. The most recognizable difference would be the size of the printed circuit boards that result from using the different styles.
Surface mount technology has made it possible to create much smaller printed circuit boards despite the increase in the number of pins placed on their surfaces. Conversely, space constraints have always been an issue for PCB assembly which uses through-hole mounting.
Through-hole mounting requires the use of larger components. This significantly lessens the amount that can be placed on any single surface area. In contrast, since surface mounting technology makes it possible to directly mount leadless components onto the surface, this process is better able to maximize the amount of surface area of both sides of the printed circuit board.
Another edge that surface mount technology has over through-hole mounting is that it is able to make PCB assembly a more cost-effective process. It makes use of less components thus making it possible to create more finished products without needing to invest more on individual parts.
Likewise, the compact size of the printed circuit boards created using surface mount technology makes it possible to acquire a higher circuit speed. Although they might be smaller in size when compared to the printed circuit boards made using through-hole mounting, they are actually able to offer higher performance quality.
Nevertheless, the main disadvantage of surface mount technology is the larger amount of initial capital that should be invested in machinery and actual PCB assembly. Naturally, it requires the use of more advanced technology, design, and production compared to through-hole mounting.
In the end, both mounting styles will most likely remain in continued use. Through-hole mounting will be preferred for printed circuit board testing and prototype creation while surface mount technology will find its niche in mass production.