Detailed Process Flow Analysis of PCBA

The detailed manufacturing process for PCBA primarily includes the following steps:

1,PCB Design and Fabrication

Using professional EDA software to draw circuit schematics and PCB layout diagrams, determining component placement, routing rules, and layer stackup.
Creating conductive traces on the insulating substrate through chemical etching, laser cutting, and other processes. Drilling holes for component mounting, followed by cleaning and inspection to ensure the PCB is defect-free.

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2,Component Procurement and Inspection

Procure resistors, capacitors, inductors, diodes, integrated circuits, and other components according to design documents (BOM).
Upon arrival, conduct visual inspections, dimensional measurements, and electrical performance tests on components to ensure compliance with design requirements. Non-conforming components must not be used in production.

3,SMT Assembly

Solder Paste Printing: Apply uniformly mixed solder paste onto PCB pads via a stencil. This process demands precise solder paste thickness, coverage area, and placement to prevent issues like bridging or insufficient solder.
Component Placement: Use automated placement machines to precisely position components onto the PCB according to pre-programmed coordinates and orientations. High-speed machines handle small-sized components, while universal machines process irregularly shaped or high-precision components.
Reflow Soldering: The assembled PCB enters a reflow oven. Through four stages—preheating, temperature stabilization, reflow, and cooling—the solder paste melts and solidifies, achieving the bond between components and the PCB.
AOI Inspection: Automated optical inspection equipment examines solder quality, detecting issues such as cold solder joints, short circuits, component misalignment, or reverse orientation. Defects are promptly identified and reworked.

4,DIP Component Assembly

For components unsuitable for SMT installation (such as large capacitors, connectors, sockets, etc.), manual or automated insertion is performed by inserting component leads into PCB through-holes.
After insertion, components are secured via wave soldering or manual soldering. Wave soldering requires precise control of wave height, speed, and flux application volume to ensure soldering quality.

5,Testing and Debugging

ICT Testing: Verifies PCB circuit connections using automated in-circuit testers to detect open circuits, short circuits, and abnormal component parameters.
FCT Testing: Powers the PCBA to simulate real-world usage scenarios, testing functions such as signal transmission, voltage stability, and logic operations to ensure compliance with design specifications.
Aging Testing: Subjects the PCBA to prolonged power-on testing, simulating user usage patterns to observe failure occurrence and evaluate product reliability.

6,Cleaning and Protection

Remove contaminants such as residual flux and solder dross from the soldering process to prevent corrosion of the PCB and components.
Apply conformal coating (moisture-proof, dust-proof, corrosion-proof) or perform potting as required to shield the PCB from environmental factors.

7,Final Assembly and Packaging

Assemble tested PCBA boards with enclosures, structural components, displays, and other parts into complete electronic products.

Pack finished products using anti-static and shock-resistant materials, label with product information and batch numbers, then prepare for shipment or subsequent processing.

The above process may be adjusted based on product type and manufacturing requirements. Certain steps may be omitted or specialized processes added for specific products (e.g., X-ray inspection, laser marking).