The world of electronic manufacturing changes regularly, and as a result – fabricators must select one of two approaches in fabricating electronic components which are the Surface Mount Technology and Through-Hole Assembly methods. Each method brings its own set of advantages and drawbacks wherein you will have the final say on which manufacturing approach is geared to your standards and budget.

In this article, we’ll be taking a look at the nuances between SMT assembly and Through-Hole Assembly and the criteria that you’ll use as a basis to make the right decision on which manufacturing approach you’ll utilize for your project.

Surface Mount Technology (SMT): An Overview

Definition of Surface Mount Technology

To begin our discussion, let’s learn what Surface Mount Technology is. SMT assembly is a process wherein electronic components are mounted directly onto a PCB’s surface through assembly machinery which an operator programs. As a result, this facilitates a fast-paced production which allows the creation of many surface-mounted circuit boards in a short timeframe.

Key Traits of SMT Assembly

• Faster production setup – Compared to Through-Hole assembly, SMT assembly’s production setup facilitates fast-paced mass-production of printed circuit boards. This trait is what makes it favorable for factories or facilities that are required to mass-produce PCBs for different clients from different niches.

• High component density, small board size – Printed circuit boards that are made through this method of assembly are far smaller than their through-hole-made counterparts. That’s because the circuit board’s surfaces contain a very high density of electronic components which maximizes the use of the allotted space of the printed circuit boards

• Flexible application – Compared to through-hole boards, SMT-assembled PCBs are quite ubiquitous as they are utilized in most applications – usually in domestic devices or consumer goods. These items where SMT-assembled circuit boards are integrated into can range from kitchen appliances to your phone.

• Can facilitate more connections – Aside from their density, SMT-assembled boards are also known for their capability to accommodate more connections as components can be placed on both the front and back sides of the printed circuit board. As a result, there are more connections possible for every printed circuit board that works as intended.

• Requires specialized tools and expert-leveled operators – SMT-assembled PCBs will require more care in the process of manufacturing them due to the compact sizes of the printed circuits requiring more attention to ensure that the end product isn’t defective. To ensure that outcome, SMT assembly factories will be required to invest in specialized tools for manufacturing, assembly, and repairing, as well as hiring expert operators who will oversee the manufacturing process.

Through-Hole Assembly: An Overview

Definition of Through-Hole Assembly

Before we delve into selecting the ideal assembly method for your project, let’s understand what

is through-hole assembly first. The through-hole method of assembling printed circuit boards involves drilling holes into the board’s surface. Once the holes are set, leads are inserted into the drilled holes before the components are installed and soldered on them. This method of assembly is significantly slower due to the added steps in installing the components but still has a key niche to fill in the world of electronics.

The Key Characteristics of Through-Hole Assembly

• Provides clients with specialized circuit boards – Despite the limited range of designs that through-hole assembled circuits have compared to SMT assembly-made circuit boards, it fares well in electronic setups that require a PCB that can function in specific conditions – say for example, a through-hole assembled PCB that is meant for use in electrical circuit setups that has a high heat dissipation for use in an industrial configuration.

• Reliable and resilient – Compared to the mass-produced SMT-assembled boards, through-hole assembled PCBs are more reliable due to the components being embedded onto the surface of the board through drilled holes and leads which also keeps the component intact. As a result, through-hole assembled boards have a very robust connection making the PCBs ideal for intense work environments ranging from military and aerospace applications to industrial use. On top of that, through-hole assembled boards sport better durability due to their designs having a high heat and stress tolerance.

• Easier repair time and adjustability – Unlike their SMT assembly counterparts, the PCBs made by through-hole assembly methods are easier to repair or operate manually. That’s because the key components embedded on the PCB are easier to replace or modify their positioning when necessary. In addition to what’s stated, the parts are easy to discern and identify so if a component on the PCB is defective; all it takes is to remove the defective part and replace it with a functioning version.

Factors to Consider in Selecting the Manufacturing Method

Now that we’ve covered the two methods of assembling circuit boards; let’s cover next the factors that you’ll need to consider in selecting which method best suits your project. Listed below are the factors that could play into choosing whether you will settle for SMT assembly or through-hole assembly for your future PCBs:

1. Costs of your Project

The first factor that comes into play in making the right choice for your PCB project is its cost. Are you willing to invest a lot of money for a specialized printed circuit board or will you settle for a PCB that can be applied in a myriad of situations? You should also determine how much is the total costs of the materials and components that will be used in your project.

These factors related to the project’s costs should help whether you should opt for SMT assembly or through-hole assembly.

2. Performance or Quantity

The next factor that comes into play whether you should choose SMT assembly or through-hole assembly is whether you value the quantity or the performance of the printed circuit board. If your goal is to produce as many printed circuit boards to meet the needs of many devices, then you could opt for SMT assembly.

However, if you value performance more – then you can consider aiming for through-hole assembly instead. Keep in mind though, that SMT-assembled circuit boards do still hold a solid performance which we’ll explore that nuance in the next criteria.

3. Choosing Between Flexibility or Specialization

If you’ve factored in the performance of the PCBs for your project, then another layer of nuance comes into play – which is choosing between flexibility or specialization. If your project aims to turn the PCBs into a size-fits-many solution for different devices then you could opt for SMT assembly. As stated earlier, the best example of a flexible-use printed circuit board are domestic and everyday electronic items that we use such as smartphones, televisions, and the like.

However, if your electronic configuration calls for a specific circuit board; say for example – if your work environment favors a resilient PCB that can withstand intense amounts of workloads, mechanical stress, and electrical flow – you would want to settle with through-hole assembly instead of SMT-assembled boards as they could deteriorate fast in these types of working conditions. Notable examples of these intense work conditions where through-hole PCBs see use are automotive factories and industrial plants; aside from military and aerospace applications.

4. The Project’s Intended Application

The last hurdle you’ll need to factor into your project whether you should settle for SMT assembly or through assembly is the intended application of your project. Is your project intended for use in consumer products or everyday items? If that’s the case then SMT assembled PCBs are your best bet.

However, if your project’s intended use is for specific niches or uses – for example; printed circuit boards for use in high-powered lighting, or to power the avionics inside a plane then utilizing through-hole assembled circuit boards could be the way to go.

Make the Right Decisions to Bring Your Project to Reality

To sum up what we’ve covered – there are two ways a printed circuit board is manufactured; namely through SMT assembly or through-hole assembly. To ensure that your project will work as intended for its target niche, you should consider the costs, quantity, or performance, its role whether it is flexible or specialized, and its intended niche.

Putting together the manufacturing methods and the factors that you need to consider will ensure that your electrical project is brought to reality.