Advantages and Disadvantages of Surface Mounting Technology

28 Mar.,2024

 

Introduction:

Surface-mount technology (SMT) is a method for producing electronic circuits in which the components are mounted or placed directly onto the surface of printed circuit boards (PCBs). An electronic device so made is called a surface-mount device (SMD). In industry, it has largely replaced the through-hole technology construction method of fitting components with wire leads into holes in the circuit board. Both technologies can be used on the same board, with the through-hole technology used for components not suitable for surface mounting such as large transformers and heat-sinked power semiconductors.

Advantages of SMT:

1)     Realize Miniaturization

The geometric size and volume occupied by SMT electronic components are much smaller than that of through-hole interpolation components, which can be generally reduced by 60%~70%, and some components can even be reduced by 90% in size and volume. At the same time, the weight of components can be reduced by 60%~90%.

2)     High Signal Transmission Speed

SMT assembled components are not only compact in structure, but also high in safety density. The assembly density can reach 5.5~20 solder joints per square centimeter when the PCB is pasted on both sides. SMT assembled PCBs can realize high speed signal transmission due to short circuit and small delay. At the same time, SMT assembled PCBs are more resistant to vibration and impact. This is of great significance to realize ultra-high speed operation of electronic equipment.

3)     Good High Frequency Effects

Because the components have no lead or short lead, the distributed parameters of the circuit are naturally reduced and the RF interference is reduced.

4)     SMT is beneficial to automatic production, improving yield and production efficiency.

The standardization, serialization and consistency of welding conditions of chip components make SMT highly automatic. The component failure caused by welding process will be greatly reduced and the reliability will be improved.

5)     Low Materials Cost

Due to the improvement of production equipment efficiency and the reduction of packaging material consumption, the packaging cost of most SMT components has been lower than that of THT components with the same type and function. Consequently, the sales price of SMT components is lower than that of THT components.

6) Simplify the Production Process & Reduce the Production Cost.

When mounting on the PCBs, the leads of components need not be bent, shaped or cut short, so that the whole process is shortened and the production efficiency is improved. The processing cost of the same functional circuit is lower than that of through-hole interpolation, which can generally reduce the total production cost by 30%~50%.

Disadvantages of SMT:

1)    Generally, the power is small.

2)    Small volume.

3)    Easy to broken.

4)    High requirements for soldering technology. Easy to appear “Pseudo Soldering”, "crater", leak of soldering, bridge (with tin), "Tombstoning" and other phenomena.

5)    Components are easy to be dropped or damaged when installed.

6)  It is not easy to use visual inspection, which is difficult to test.

7)  Miniaturization and numerous solder joint types complicate the process and inspection.

8)   Large investment in equipment

9) Technical complexity requires high training and learning costs.

10)  Rapid development requires continuous follow-up.

PCB assembly Capabilities in PCBWay

Our state-of-the-art assembly equipments enable us to meet all your PCBA needs under one roof in an inexpensive way, our Printed Circuits Boards Assembly Capability includes but not limited to what are listed below, as we are updating our equipments constantly to keep us on the cutting edge. If your PCB Assembly demands are beyond these capabilities, please contact us at service@PCBWay.com, we will respond if we can do or not within 24 hours.

SMT Simple Process: https://www.youtube.com/watch?v=yOsDKwszlvE


For more information Surface Mount Technology, please get in touch with us!