Benefits / Advantages of Surface Mount Technology (SMT) Over Through-Hole

Surface mount components are small and can be mounted on either side of the PCB and have gained widespread usage in electronics. The benefits of SMT or Surface Mount Technology are available in both design and manufacturing.

Design Benefits of Surface Mount Technology

Among the most important design-related benefits are significant savings in weight and real estate and electrical noise reduction. A Surface Mount Component can weigh as little as one-tenth of their conventional thru-hole counterparts. This causes a significant reduction in weight of the Surface Mount Assembly (SMA). Because of their smaller size, surface mount components occupy only about one-half to one-third of the space on the printed circuit board.

Since all electronic components are not available in surface mount, the actual area savings on a board will depend on the percentage of through-hole components replaced by surface mount components. Depending on the component mix, the three types of surface mounting discussed in my previous article provide different levels of benefits.

SMT also provides improved shock and vibration resistance as a result of the lower mass of components. Shorter lead lengths of Surface Mount Components offer benefits of lower parasitic that reduces propagation delays and reduces package noise.

In addition to design benefits, SMT also provides many manufacturing benefits. These benefits include reduced board cost, reduced material handling cost, and a controlled manufacturing process. Routing of traces is reduced, size of the board is reduced, and number of drilled holes is also reduced. A smaller board with fewer drilled holes will naturally cost less. If the functions on the surface mount board are not increased, the increased interpackage spacings made possible by smaller surface mount components and a reduction in the number of drilled holes may also reduce the number of layer counts in the printed circuit board. This will again lower the board cost.

The above benefits of Surface Mount Technology don’t necessarily means that SMT assembly will always cost less. It depends when and how SMT is used.