PCBA File Requirements: Gerber, BOM, Centroid and Assembly Drawings

Four File Sets, One Complete Order

1. Bare-board fabrication files. Gerber RS-274X (all copper, mask, legend and paste layers) plus Excellon drill files - or a single ODB++ / IPC-2581 archive. Include the fabrication drawing if stackup, impedance or tolerances are special.

2. BOM (bill of materials). Provide as .xls/.xlsx/.csv with these columns:

• Line / Item number
• Manufacturer part number (MPN) - exact, no abbreviations
• Reference designators (R1, R2, C10...)
• Quantity per board
• Package / footprint (0402, SOT-23, QFP-64...)
• Description or value (10uF 16V X5R 0805)
• Preferred brand (optional)

3. Centroid / pick-and-place file. CSV or .txt, one line per component with: reference designator, X/Y coordinates (mm, board origin bottom-left preferred), rotation (deg, per your CAD library), side (top/bottom).

4. Assembly drawing (optional but valuable). PDF marking polarity, pin-1 indicators, shield mounting, hardware torque and anything not obvious from the centroid.

Common Gaps We Fix Daily

• Paste layer missing for BGAs - we regenerate from copper with your approval
• Centroid rotations differing from CAD library - we verify against footprint silks
• MPNs with obsolete status - we propose cross-references before sourcing

Files missing or messy? Do not stop - upload what you have and the engineering team returns a gap list with the quote. Start here.