Surface Mount Assembly

Surface Mount Assembly (SMT)


ESD’s electronic assembly facility operates in a controlled anti-static environment. Our fully automated SMT machines can equally supply low to high volume production in accordance with our customer’s requirements.

We have several automated pick and place machines. All of which can place fine pitch SMT components at high speed. We populate single or double sided PCBs. The first side of the PCB is fully populated and soldered before processing the second.

Our reflow oven has several temperature zones to enable gentle heating, and cooling of the PCBA. We program the temperature and speed through each zone based on data which includes the PCB material and the components on the board. This care and attention to detail is to ensure the quality and joint integrity on each SMD assembly.

Our AOI (Automated Optical Inspection) machines inspect each surface mount assembly. These machines check the markings on each component. This confirms that the type, value and orientation of the component is correct according to the pre-programmed values.

Component Sourcing

Customers are welcome to free-issue components or pcbs for their assemblies. If you prefer, ESD’s experienced purchasing team can buy some or all of your components and PCBs for you, saving you time and the headaches that are often part of this process. We use established local & global suppliers to procure the components specified on your BOM. Our large stock of standard components is available to customers. We can advise you which of these are on your bom if you prefer to part-source.


Customers can prove their designs using ESD’s PCB prototype assembly service. This service includes sourcing the PCB and components if required, as well as the electronic assembly. We can also provide feedback about the PCB layout in terms of design for manufacture on request.


At ESD we process a variety of PCB materials, from flexible PCBs to standard FR4 and Aluminium boards. The size of the PCBs handled varies from very small to panels upto approximately A3 in size (and occasionally larger). The PCBs can be Single or Double sided.

How Does SMT Assembly Work?

The solder paste is evenly applied to the PCB through a paste stencil. The PCB then goes into a pick and place machine which has components for the specific electronic assembly. The robot inside the machine then selects the specified components, identifies and places them in their pre-programmed locations. The PCB next travels on a conveyor through a reflow oven to be cooked.

Advantages of  SMT

SMT produces electronic circuits with components mounted directly onto the surfaces of the PCB. Components are generally smaller than their through-hole counterparts because they sit on pads instead of legs.

  • A higher number of components fit into the same space (when compared to through hole).
  • A Simpler and faster assembly process shortens the overall production time and therefore cost.
  • The process will automatically correct minor placement errors.
  • The PCB can be smaller than an equivalent through hole board
  • The internal robot automatically places components onto each side of the PCB.
  • Less holes are required in the PCB.