How does SMT work?

So in practice, SMT is used within the manufacturing of PCB electronics. The electronic components are placed and soldered using fully automated production lines. Roughly speaking, you can divide the whole process into three steps:

• A custom-made paste stencil is used to apply solder paste to the locations where the components will be placed on the board.
• Then the components are placed on the PCB fully automatically via SMD stations.
• After placing the components, the assembled circuit board goes through a pass-through oven so that the solder paste cures and the components are secured in place.
  

The benefits of SMT

Surface Mount technology has a number of advantages. Not only the volume of electronic components but also the geometric dimension can be many times smaller than with continuous components. Another advantage is the high signal transmission rate. If the PCB is assembled on all sides, an assembly density of 5-5-20 solder joints per square centimeter can be achieved. An additional advantage is a high-frequency effect, as there are no leads or they are very short. This reduces RF interference and reduces distribution parameters. The SMT technology is ideal for automatic production, thereby also improving yield and product efficiency. Other advantages of SMT technology are:

• Fewer or no holes needed in the circuit board for mounting components
• There is lower resistance and inductance at a joint. 
• There are lower initial costs and less time to set everything up for mass production. This is possible because automated production lines are used.
• Higher component density, many more compounds per component possible. 
• Components can be placed on either side of the circuit board.
• Under shock and vibration conditions, improved mechanical performance is possible.