Even though most SMT soldering is achieved through reflow, some assemblies require that some of the Surface Mounted Devices (SMDs) on a board, such as chip components, must be wave soldered. Often, these passive components are on the bottom side of a PCB and are held in place by dots of adhesive. In many cases the top-side SMDs are then attached with a reflow oven pass. Much depends on the design of the product and the components used.
Electrovert® Electra™, VectraElite™, and VectraES™ wave soldering systems offer several features that increase process capability and flexibility, enabling wave soldering of SMDs.
Omega wave: Electrovert Omega wave features an oscillating vibration in the main wave that promotes wetting around small components.
Rotary chip wave: The rotary chip wave promotes wetting to pads and eliminates skips and shadowing caused by taller SMT components. The feature includes a programmable rotary rpm to control the wave action.
Soldering in Nitrogen: The use of nitrogen improves wetting ability. This applies to both through-hole components and SMDs. Nitrogen soldering features include UltraFill™ boundary-type N2 soldering and a nitrogen tunnel (inerts the entire solder pot area).