About PCBA

PCBA (Printed Circuit Board Assembly) involves the process of assembling electronic components onto a bare PCB, giving it functionality. The main steps in PCBA include component placement, soldering, inspection, and testing. Greatpcb ensures strict quality control at every step.

PCB Assembly Service Process

1. Submission Of Documents And Material Preparation

  • Submission of Documents: Customers provide the necessary design files, such as Gerber files, BOM (Bill of Materials), complete PCB files, and placement information.
  • DFM Check: Early detection and resolution of potential issues to improve efficiency, reduce costs, and ensure product quality.
  • Material Procurement: Greatpcb procures the necessary materials based on the design files, providing PCB and PCBA manufacturing services.
  • Material Inspection: Quality inspection of the procured components and materials.

2. Solder Paste Printing

  • Stencil Preparation: Create a stencil based on the design files for solder paste printing.
  • Solder Paste Printing: Secure the PCB on the printing machine and apply the solder paste evenly onto the PCB pads through the stencil. Apply one-third of a bottle (500g) of solder paste at a time, in multiple small applications, to ensure the activity of the solder paste and prevent flux evaporation.

3. Component Placement

  • Programming: Program the pick-and-place machines according to the design files to automatically place the components.
  • Inspection: The machine vision system automatically detects issues like bent leads or missing components.
  • Placement: Prepare materials according to the BOM and placement file, and the pick-and-place machine identifies mark points and coordinates for precise placement of components onto the PCB pads.

4. Reflow Soldering

  • Visual Inspection: Operators inspect each component’s leads to ensure correct placement before proceeding to the reflow soldering process.
  • Reflow Soldering: Use high-temperature hot air to reflow and melt the solder paste, bonding the components to the PCB. Conduct a thermal profile test every 12 hours to ensure soldering quality.

5. Automatic Optical Inspection (AOI)

  • Inspection: Compare sample images with finished product images to detect solder quality, solder joint structure, component markings, and placement accuracy. After AOI, feedback is provided to SMT technicians for adjustments.

6. X-Ray Inspection (If Applicable)

  • Inspection: Used for complex components that cannot be inspected by AOI or visual methods. X-ray inspection checks the internal quality of solder joints.

7. Final Inspection And Functional Testing

  • Testing: Assess the electrical performance, functionality, and behavior of the PCB under different environmental conditions (temperature, humidity). This includes EMC (Electromagnetic Compatibility) testing and durability testing. Products must fully meet standards before proceeding to the next step.

8. Packaging And Shipping

  • Packaging: Optionally use anti-static bags, wrap the PCBs in foam for multi-layer protection, then box them up.
  • Shipping: Use international logistics services like FedEx, DHL, UPS, or EMS for delivery.