PCB Preparations for SMT Assembly
The electronics industry is rapidly evolving with IoT and wearable devices driving the trend which requires smaller PCB with more features than before. In these devices, PCB board must be designed for SMT assembly and in accordance with the best design practices to minimize defects in the final products.
Before manufacturing printed circuit boards, make sure that your SMT assembly has been optimized. Here are some helpful tips.
Components Placement-- The basic criteria for component placement must adhere to easy SMT assembly practice, also follow troubleshooting purposes. Components should be aligned and maintain a similar orientation throughout the design.
Fiducial Markers-- Make sure that global fiducial markers is placed on the correct and accurate placement of the assembly machine. If your design consists of a Quad Package surface mount components like QFP, QFN or BGA, or if you also need to include a local fiducials as well, please contact your SMT assembly supplier to do double check.
Mask Vias under BGA-- If your design contains BGA components, make sure that any vias below the component are properly masked. This prevents solder balls from touching or smearing on the via, and creating unintended connections that are unable to spot visually.
Place SMT Components on the Same Side-- Placing all surface mount components on the same side may not make any technical difference, but you can save money when your PCB board is sent for assembly. It is very convenient, only one stencil is needed, but the process of component installation and soldering can be reduced.
Via under Component Pads-- While via under component pads can contribute to thermal management, it may also weaken the solder joint between component legs and pads, or leak solder into vias causing irregular solder volume. If possible, avoid having via under component pads.