SMT manufacturing equipment is used to populate printed circuit boards (PCB) that use surface mount technology (SMT). This includes soldering machines, ovens, component placement, paste depositors and screens, and stencils. SMT manufacturing equipment enables PCB manufacturers to place more features on smaller boards without having to secure components with through-hole wire leads.
SMT manufacturing equipment uses soldering and adhesive equipment to secure components directly to the surface of a printed circuit board. SMT manufacturing equipment allows both sides of a PCB to be printed with circuits and fitted with components. SMT production starts with an SMT machine that coats a PCB with a thin layer of solder paste guided by the use of stencil. Each SMT component is placed on the solder paste, which consists of flux particles and solder particles. The PCB passes through a series of reflow ovens which melt the solder paste and burns off the flux particles. Surface tension in the liquid solder allows the components to stay in place on the solder pads attached to the PCB assembly while the solder cools. PCBs that are printed on both sides may use adhesive dots to secure the components on the remaining side. The adhesive is cured by using low heat ovens or ultraviolet (UV) radiation.
SMT manufacturing equipment provides simple SMT assembly by using smaller components and eliminating problems with lead resistance and inductance, and improving performance in high frequency applications. SMT manufacturing equipment may also include infrared lamps or hot gases to reflow solder for adding additional components. Any components that are heat-sensitive or irregularly shaped may be soldered on the PCB by hand.