SMT Assembly Considerations
Surface mount technology is the widely-used alternative to through-hole printed circuit board design and manufacturing practices. Today an increasing majority of PCB devices are available as SMDs or packages, making the adoption of SMT board designs and manufacturing practical and cost-effective.
To gain the most significant advantage in fabrication, SMT construction must be as highly mechanized as possible. Assembly advantages in SMT manufacturing are as follows:
1. Hole drilling is nearly or totally eliminated, with the SMDs being connected directly to the board surface.
2. Reliability is enhanced, since there is no requirement to fit component leads through holes for subsequent soldering in place. Soldering SMDs to surface pads is simpler and faster, reducing assembly time while also improving quality.
3. SMT assembly is highly automated, speeding production and reducing turn-around for customers.
4. Through-hole fabrication required careful alignment with drilled holes, and often pre-forming of the leads to accommodate specific PCB layout and component placement. SMT assembly eliminates the majority of SMD placement intervention, allowing for more automation and thereby reduced cost.