PCBA Special Reminders for a Smoother Assembly Order

Submit the Gerber file for bare-board fabrication, an Excel BOM, and a centroid file with component coordinates and rotation data. Include an assembly drawing that shows polarity, special assembly notes, and mechanical requirements.

If the order requires functional testing, include the functional test specification and test fixture. If programming is required, include the firmware file. Incomplete files can delay order processing and the start of production.

Each BOM line should include the manufacturer name, manufacturer part number, description, package, quantity, and designator. Check every manufacturer part number before submission because an incorrect number can lead to incorrect component sourcing and assembly.

Mark alternative components clearly and assign a priority level to each alternative. Mark components that should not be placed with “DNP” (Do Not Place). Moisture-sensitive, electrostatic-sensitive, and other special-handling components should also be identified in the BOM.

Show the polarity of polarized components on both the PCB silkscreen and the assembly drawing. This includes diodes, electrolytic capacitors, ICs, and connectors.

Keep the Gerber, BOM, and centroid file consistent for component package, pad size, and coordinate data. Add test points for electrical and functional testing, with a test point diameter of at least 0.8 mm. Maintain sufficient clearance around BGA, QFN, and fine-pitch components to support rework and inspection.

The available choices are full turnkey sourcing, consigned components, and partial consignment. With full turnkey sourcing, the supplier sources all components from authorized distributors and original manufacturers according to the BOM. With consigned components, you provide all components and the supplier provides assembly. With partial consignment, you provide critical components and the supplier sources the remaining parts according to the BOM.

Confirm the sourcing option before order confirmation. This helps prevent duplicate sourcing and processing delays.

Moisture-sensitive components should be kept in a dry cabinet and baked according to the component manufacturer's specification before assembly. Electrostatic-sensitive components require full ESD protection throughout the assembly process. Identify components with special storage requirements and include their storage conditions.

Tape-and-reel packaging is recommended for automatic placement. For consigned components, provide complete packaging and original labels to reduce quality issues associated with improper storage.

Before requesting a quotation or order review, send the Gerber, Excel BOM, centroid file, assembly drawing, and any applicable test fixture or firmware together, then identify the sourcing option and special-handling parts.