1. Solder Paste Application:
   The process starts by applying solder paste to the designated pads on the PCB using a stencil. This paste contains tiny solder balls and acts as the adhesive for components.

2. Component Placement:
   Automated pick-and-place machines then precisely position surface mount components (SMDs) onto the board, aligning them with the solder paste.

3. Reflow Soldering:
   The board passes through a reflow oven where controlled heating melts the solder paste. As it cools, the solder solidifies, forming reliable solder joints that electrically and mechanically bond the components to the PCB.

4. Through-Hole Soldering (if needed):
   For components that require through-hole mounting, wave soldering or manual soldering techniques are used to attach these parts securely.

5. Inspection and Testing:
   After soldering, the assembly undergoes rigorous inspection using Automated Optical Inspection (AOI), X-ray, or manual checks to detect soldering defects or misaligned components. Functional testing ensures that the board meets all performance specifications.

6. Cleaning and Coating:
   Boards are cleaned to remove any residual flux and, if necessary, a conformal coating is applied for protection against moisture, dust, and other environmental factors.

7. Final Quality Assurance & Packaging:
   The assembled PCB is given a final quality check before it is packaged and shipped to the customer.

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