SMT or Through Hole Technology？Which is Better for Your Project？

When designing and manufacturing electronics, one of the most important steps is selecting the appropriate assembly method. Nowadays we have through-hole technology and surface mount technology, which become the industry standards and are the two main approaches. The surface-mount technology (SMT) uses components that are perfectly aligned with the PCB surface. On the other hand through-hole technology (THT) uses leads that are placed into pre-drilled holes in the PCB and thereafter soldered.

Considering aspects including component kinds cost, manufacturing complexity and application. In this article will evaluate SMT versus Through-Hole Technology in depth to assist you in making an informed decision for your PCB project.

1.    What is Surface Mount Technology (SMT)

When using Surface Mount Technology (SMT) the components are mounted directly onto the PCB's surface. The SMT technique is well-suited for high-density boards because it doesn’t employ holes to hold component leads. The components produced by the process have flat, short or nonexistent leads. It comes in a variety of bundles, each with its own unique set of features, including pads, pitch, and more. Automatic pick and place machines may directly employ SMTs, simplifying the assembly process. They are ideal for miniature electronics because of their small size and ability to be put on either side of the printed circuit board (PCB). As a result of smaller components and boards, the total cost is reduced as well. Smartphones, laptops, Internet of Things devices, and medical electronics all make use of SMT components.

2.    What is Through-Hole Technology (THT)?

The conventional method of assembly, known as Through-Hole Technology (THT). It involves inserting component leads into PCBs that have already been drilled and then soldering them on the other side. Their size and weight are noticeable. There is always room for product prototype and revisions, even though THT are not employed currently in contemporary PCBs. Reason being, they work with breadboards and general purpose PCBs. The vast surface and improved thermal profile of TH components make them ideal for applications like power electronics, however, where heat dissipation remains a major challenge.

3.    Surface Mount Technology (SMT) Assembly:

Component Placement and solder application: The first step in surface mount technology (SMT) assembly is to use a stencil to apply solder paste to the PCB pads. After that the solder paste is covered with small surface-mount components (SMDs). This all is done with the help of automated pick-and-place devices.

Soldering: To solder the components together the board is heated in a reflow oven. It is done until the solder is melted and the connections are not solid enough. Specialised machinery including reflow ovens, stencil printers and pick-and-place systems used in assembly. And automated inspection tools are necessary for SMT.

With SMT less manual labour is required and production speeds are increased because most of the job is automated. Because of this it is perfect for mass production of small electrical products like IOT related. Smartphones, laptops, and automotive electronics are just a few of the many sectors that make use of SMT because of its decreased mistake rate and faster assembly time.

4.    Through-Hole Technology (THT) Assembly:

Component Placement and solder application: In THT assembly, component leads are inserted onto the PCB through pre-drilled holes. After the drilling is done, the components can be inserted either manually or semi-automatically into the holes. .

Soldering: After that, the soldering process can be carried out either manually or with the use of wave soldering machines, depending on the component. Tools for testing connections, wave soldering systems, hand soldering tools, and drilling machines are also part of the equipment utilised.

THT assembly is more suitable for prototypes, low-volume manufacturing, or components requiring greater mechanical strength than SMT since it requires more manual work and takes more time. Power supplies, connections, and other big industrial machinery frequently utilise it because of its long lifespan and reliability.

5.    When to Choose:

SMT:

●       Your design requires miniaturization.

●       High-density component placement is necessary.

●       You want to reduce manufacturing costs for high-volume production.

●       Your application involves consumer electronics, medical devices, or wearables.

Through-Hole:

●       Your project involves mechanical stress or harsh environments.

●       Power circuits with large components (e.g., power supplies, transformers).

●       The project is a prototype or low-volume production where manual assembly is feasible.

●       You’re building aerospace equipment.

These days, through-hole and surface-mount components work hand in hand to construct most printed circuit boards. By combining the two approaches, designers may reap the advantages of each. Use SMT for passives and high-density integrated circuits and THT for mechanical and power-critical components.

SMT vs Through-Hole: Key Differences

Conclusion: Which is Better for Your Project?

Whatever your project calls for, SMT or Through-Hole Technology is the way to go. In order to help you make a choice, the blog contains all the necessary information. We can, in general, say that:

●       Choose SMT for compact and consumer-oriented electronics.

●       Choose THT for robust and high-reliability mechanically stressed assembly

In many cases, the optimal option is a hybrid strategy. Which combines both technologies for products that are both adaptable and trustworthy.

To make this process easier, JLCPCB provides professional SMT and through-hole assembly services with fast turnaround, reliable quality, and affordable pricing. Start your PCB assembly today