After a board passes through fabrication, it will be handed off to an assembly team so that components can be mounted on the bare PCB. The fabrication files we discussed in Lesson 2 of this unit will be used to prepare tooling for the assembly process. The critical files used in PCB assembly are the pick-and-place file, and the solder paste mask file in your fabrication data (Gerber files, ODB++, or IPC-2581 files). With these files, the assembler can prepare a large batch of bare boards to pass through automated assembly and soldering processes.

Once the design is assembled, it may pass through a round of functional testing and inspection to ensure the assembly process was completed correctly. If the board is for an embedded system that needs some firmware, the design may require flashing on the assembly line so that code can be burnt into the system’s memory. We’ll discuss all of these aspects of PCB assembly in this lesson.