Surface Mount Assembly

Surface Mount Assembly (SMT)


ESD’s electronic assembly facility operates in a controlled anti-static environment. Using our fully automated SMT machines we are able to supply low to high volume production.

We have several automated pick and place machines, all of which can place fine pitch SMT components at high speed onto PCBs. We populate single or double sided PCBs. Each machine can hold approximately 60 different component types, depending on the component shape and size.

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 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, looking at the markings on each component. This inspection 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 and/or pcbs for their assemblies. Alternatively ESD’s experienced purchasing team can buy some or all of your components and PCBs for you, thus saving you time and the headaches that are often part of this process. We use established local & global suppliers to buy the components specified on your BOM. Our large stock of standard components is also 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, in addition ESD can source the PCB and components if required.


At ESD we can process a variety of PCB materials including flexible PCBs, standard FR4 and Aluminium boards. We set up the machines to process PCBs in many sizes from very small to approximately A3 in size (and occasionally larger). The PCBs can be Single or Double sided, and multiple layered.

Our production line set up is flexible. We can use multiple machines in series for large projects, or run many smaller projects simultaneously.

How Does SMT Assembly Work?

We use our customer’s gerber files to program the machine, and these together with the bom specify the components we load into the machine. The solder paste is evenly applied to the PCB using a paste stencil before the PCB is loaded into the SMT machine. The internal robot selects the specified components according to the program, identifies and orientates each one before and placing them in their allotted locations. The populated PCB travels on a conveyor through a reflow oven to cook the solder.

The surface mount components on the first side of the board are fully soldered before starting work on the second side.

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 a lot 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.