Is Surface Mount Cheaper Than Through Hole?

Waseem Jalal

In the ever-evolving world of electronics, printed circuit boards (PCBs) play a pivotal role. Over the years, PCB technology has witnessed a significant transformation, driven by the need for smaller and more efficient electronic devices. This shift has led to the dominance of surface mount technology (SMT) over traditional through-hole technology (THT) in PCB assembly. While both methods have their advantages and drawbacks, the key question remains: Is surface mount cheaper than through hole in PCB assembly?

Surface Mount vs. Through Hole: A Brief Overview

To answer this question comprehensively, let’s first delve into the basics of surface mount vs through hole technologies.

Through-Hole Technology (THT): Through-hole mounting involves inserting component leads into drilled holes on a bare PCB. It was the industry standard until the advent of surface mount technology (SMT) in the 1980s. THT components are known for their durability and stronger connections between layers, making them ideal for high-reliability products exposed to extreme environmental conditions, such as military and aerospace applications. However, THT has its drawbacks, including longer production times, higher costs, and limited component availability.

Surface Mount Technology (SMT): SMT, on the other hand, is the process of mounting components directly onto the surface of a PCB. It eliminates the need for drilled holes and allows for smaller, more compact PCB designs. SMT components are smaller and can be placed on both sides of the board, enabling higher component density and cost savings. This method is highly automated, significantly reducing assembly time and costs. SMT is the preferred choice for most PCB applications due to its efficiency and cost-effectiveness.

Cost Comparison: SMT vs. THT in PCB Assembly

Now, let’s delve into the cost comparison between surface mount and through-hole technologies in PCB assembly:

Surface Mount (SMT): SMT is generally more cost-effective than THT for several reasons:

Automated Assembly: SMT assembly is highly automated, allowing for faster and more precise component placement. Pick-and-place machines can handle thousands of placements per hour, minimizing labor costs.

Reduced Material Costs: SMT components are smaller, resulting in reduced material costs. Smaller PCBs with fewer holes lead to additional savings.

Availability of Components: SMT components are readily available in the market due to their widespread use, reducing lead times and overall costs.

Faster Production: SMT assembly is faster than THT, leading to shorter production times and lower labor costs.

Efficient Soldering: SMT solder joints are more reliable and repeatable thanks to reflow ovens, minimizing the chances of defects and rework.

Higher Volume Production: SMT is well-suited for high-volume production, further driving down costs.

Through-Hole (THT): While THT still has its niche applications, it tends to be more expensive compared to SMT due to the following factors:

Manual Labor: THT assembly often involves manual soldering, which is slower and requires more labor.

Component Availability: Finding through-hole components can be challenging as they are less commonly used in modern electronics.

Longer Production Times: THT assembly takes longer, leading to increased labor costs and longer lead times.

Component Size: THT components are larger, leading to higher material costs and larger PCB sizes.

Conclusion: Making the Right Choice

In the ongoing debate of surface mount vs. through hole in PCB assembly, cost considerations play a pivotal role. While both technologies have their merits, surface mount technology generally emerges as the more cost-effective option in modern PCB assembly.

SMT offers smaller PCBs, higher component density, shorter production times, and greater automation efficiency, all contributing to cost savings. However, there are situations where through-hole technology is still essential, particularly in applications requiring extreme durability and high-power capacity.

In conclusion, the choice between SMT and THT ultimately depends on the specific requirements of your PCB assembly project. To make an informed decision, consider factors such as project scale, component availability, production volume, and the environmental conditions your PCB will face. By carefully evaluating these factors, you can determine whether surface mount or through-hole technology is the cost-effective solution for your PCB assembly needs.

In the ever-changing landscape of PCB assembly, staying informed about the advantages and cost implications of these technologies is crucial for making the right choice in today’s electronics industry.