How is it possible that nowadays electronic devices can be made for such a low price? There are a number of factors that play a major role. One of them is efficiency and a high level of production automation. Everything a machine can do saves human labour. The application of SMT production has several major advantages. Electronic components that are used are small, often even tiny. This allows electronics to fit onto a smaller and cheaper printed circuit board (PCB). Also the enclosure can be smaller and cheaper. However the most important cost saving is caused by automatic assembly with SMD production components by a pick and place machine. A pick and place machine works fast (10.000 or more components per hour) and very accurate (better than 0.01 mm precision). Fully automatic, with minimum labour. An enormous cost efficiency can be achieved through SMT manufacturing by raising the production level per human working hour. An extra advantage of SMT production is that the weight of the SMD components are less and leads are shorter compared to through hole components (THT). Hence less mass and a shorter €arm of the force€ which results in less torque on the leads during vibration. The vibration resistance increases significantly.

What is SMT and SMD Production anyway?
SMT stands for €Surface Mount Technology€. SMT is the name of the mounting technique. It uses components with leads that are placed on the PCB instead of through the Circuit Board. When the leads go through the PCB we call it €through hole€.

SMD stands for €Surface Mount Device€. SMD is the name of the component, suited for SMT. In practice everybody talks about SMD production, being the technique or the component.

SMD mounting
The pick and place machine picks up electronic components from various feeders and places them on the correct position on the Circuit Board. The leads are pressed slightly in the solder paste. As the solder paste is sticky, the electronic components stay in position while the other components are placed.

Reflow soldering
The PCB is passed through an oven so the solder paste melts and actually solders the electronic components to the PCB.

AOI Inspection
The soldered PCBs are optically inspected for correct SMD production, assembly and soldering.

PCB Assembly Functional Test
Functional tests are used as a final manufacturing step to simulate the operating environment for the product. It provides a pass/fail determination on finished PCBA before they are shipped. An FCT's purpose in manufacturing is to validate that product hardware is free of any defects that could, otherwise, adversely affect the product's correct functioning in a system application. Test procedures vary widely according to SMT producer and control systems.