Key steps and precautions for PCBA patch processing

1. Solder paste printing

Steps: Use a steel mesh to print the solder paste evenly onto the PCB pad.

Note: The steel mesh thickness, scraper pressure and angle must be precisely controlled to prevent

 insufficient tin or bridging.

2. Component placement

Steps: Use a high-speed placement machine to accurately place SMD components on the PCB.

Note: Ensure accurate programming and unblocked nozzles to avoid offset or dropout.

3. Reflow soldering

Steps: The PCB enters the reflow oven and completes soldering according to the temperature curve.

Note: Control the preheating, reflow, and cooling curves to avoid cold soldering, cold soldering, or 

overheating to damage components.

4. AOI inspection

Steps: Automatic optical inspection to check soldering quality.

Note: Focus on checking defects such as insufficient tin, short circuits, and tombstones to improve 

the pass rate.

5. Manual soldering and repair

Steps: DIP plug-in soldering or rework abnormal solder joints.

Note: The temperature is moderate to prevent damage to the PCB or components.

6. Testing and Inspection

Steps: ICT, FCT and other tests to ensure that electrical performance meets the standards.

Note: The test fixture must be designed to match the design to ensure accurate testing.

7. Cleaning and Packaging

Steps: Remove residual flux and pack with anti-static treatment.

Note: Moisture-proof and anti-static to ensure safe transportation.