PCB Assembly Files: Gerber, BOM and Pick-and-Place

Normally: Gerber files, BOM, pick-and-place (centroid) file, assembly drawing, PCB specification, assembly quantity, test requirements, and special process requirements. The more complete the data, the more accurate the quote and engineering evaluation.

Gerber is a common family of PCB manufacturing data formats describing traces, solder mask, silkscreen, pads, and other manufacturing layers. The exact file set should be confirmed against the PCB fab and project requirements.

Pick-and-place files (also called centroid files) describe component reference designators, X/Y coordinates, rotation, and side, for SMT placement programming and production preparation.

An assembly drawing explains component locations, orientation, and special assembly requirements, helping the manufacturing engineer understand information that is not obvious from the BOM or coordinate data.

A BOM (Bill of Materials) lists reference designators, manufacturer part numbers, quantities, descriptions, packages, etc. An accurate BOM is the foundation for quoting, procurement, preparation, and assembly — because the manufacturer part number, quantity, alternates, and supply status directly affect procurement price, availability, and lead time.

DNI marks a BOM item that is not installed in the current production revision. To avoid procurement and assembly misunderstanding, it should be clearly marked in the BOM, assembly drawing, or manufacturing file.