In SMT prototyping and chip processing, providing the right documentation is crucial for ensuring a smooth and efficient manufacturing process. Below is a detailed guide on the necessary files that need to be submitted to the factory:
1. Gerber Files
Gerber files are essential documents exported from PCB design files by the R&D team. These files contain crucial information about the:
- Pad layer (for solder pads)
- Solder mask layer
- Silkscreen layer
- Stencil layer
The factory relies on Gerber files to create stencils and develop the SMT program. Since these layers are necessary for production, they must be provided. However, if your product is still in the R&D stage and you’re concerned about intellectual property protection, you can modify the Gerber file by retaining only the necessary layers and removing sensitive information before sharing it with the factory. Additionally, signing a Non-Disclosure Agreement (NDA) with the factory can offer further protection.
2. Bill of Materials (BOM)
The BOM (Bill of Materials) is a comprehensive list of all components used in the assembly. It serves as the standard reference for:
- Material verification upon receipt at the factory
- The creation of production programs
A BOM must clearly describe each component and its corresponding details to ensure an accurate material inspection and alignment with the production requirements.
3. Pick-and-Place Coordinates
The Pick-and-Place file describes the exact position of each component on the PCB. The file should have:
- A file extension of either .txt or Excel format
- Units in millimeters (mm) as the standard measurement
- The PCB origin point (commonly set at the bottom left corner)
This file enables the automated machines to accurately place each component in its designated position on the PCB.
4. Assembly Drawing (Placement Diagram)
The Assembly Drawing is a visual representation exported from the PCB design software, showing the pad layer and silkscreen layer. The factory uses this diagram to verify the accuracy of SMT component placements, ensuring that the parts are positioned correctly on the board during assembly.
By providing these four essential files—Gerber files, BOM, Pick-and-Place Coordinates, and Assembly Drawing—the factory can proceed with material inspection, SMT chip processing, prototype programming, stencil fabrication, and fixture creation. This ensures that the production process is fully equipped and meets the necessary standards for high-quality SMT manufacturing.