Building a PCBA (Printed Circuit Board Assembly)
1. Solder paste stenciling: A thin, stainless-steel stencil is placed over the PCB and a solder paste is applied to the board. The solder paste stencil is like a screen-printing mask, and it ensures that the solder paste is applied in the correct locations.
2. Solder paste inspection: A solder paste inspection machine is used to verify that the solder paste has been applied correctly. The inspection machine uses a camera to capture images of the PCB, and it uses software to analyze the images for any defects.
3. Component placement: A pick-and-place machine is used to place the electronic components on the PCB. The pick-and-place machine uses a robotic arm to pick up the components from their feeder strips and place them on the PCB in the correct locations.
4. Reflow soldering: The PCB is placed in a reflow oven, where the solder paste is melted and the components are soldered to the board. The reflow oven uses a controlled temperature profile to ensure that the solder melts and flows correctly.
5. Automated optical inspection (AOI): An AOI machine is used to inspect the PCB for any defects. The AOI machine uses a camera to capture images of the PCB, and it uses software to analyze the images for any defects, such as missing components, solder bridges, or cold solder joints.