- Issue Time
- Jul 28,2021
PCB is a key component of electronic components and is widely used in all walks of life. This article will introduce the specific assembly process of PCB.
PCB assembly consists of a series of complicated steps, among which there are many things to pay attention to. We must strictly follow these steps.
Application of solder paste
This is the first step in PCB assembly. Before adding components, you need to add solder paste. Minghua avionics automatic printing machine. The solder paste needs to be added to the area of the circuit board to be coated with solder. Apply the solder paste on the circuit board with the help of the soldering screen. It is placed in the correct position on the chessboard, and the runner moves over it. This allows solder paste to be squeezed through the hole and applied to the circuit board.
This is done after applying solder paste. Surface mount technology (SMT) requires precise placement of components, which is difficult to achieve by manual placement. Therefore, the components are placed on the circuit board by means of a pick-and-place machine. The PCB design information provides the location where the components need to be placed and the component information required by the pick and place machine. This simplifies pick and place programming and makes it more precise.
In this step, the actual connection occurs. After placing the components, place the circuit board on the conveyor belt of the reflow oven. The solder applied during the soldering process melts during reflow soldering. This permanently connects the component to the circuit board.
In this step, the printed circuit boards are placed on a system driven by a mechanical conveyor and pass through different areas. The PCB passes through the molten solder wave, which helps to connect the PCB pads/holes, electronic component leads, and solder. This helps to form an electrical connection. It should be noted that different selective wave soldering processes can be selected according to the number of components on the bottom surface. Different processes have different requirements for the spacing and orientation of the components. You can refer to the layout requirements of the board components.
Clean the PCB
It is very important to clean the PCB after assembly. This process helps to clean all flux residues with the help of ionized water.
Check PCB components
This is one of the most important steps in printed circuit board assembly. Techniques such as X-ray and AOI are used to determine the quality of the assembled PCB. In this step, check the circuit board for short circuits, loose solder balls, and bridges between solder balls.
Test the printed circuit board and monitor the output
This is the last step of the whole process. This step involves monitoring whether the product provides the desired output. The board is tested and analyzed for failures through several methods.
In the soldering process, the smallest variables should belong to the machinery and equipment, so they are the first to be checked. In order to achieve the correctness of the inspection, an independent electronic device can be used to assist, such as using a thermometer to detect various temperatures and using an electric meter to accurately calibrate machine parameters.
Tip: In any case, try not to adjust the machine and printed circuit board equipment to overcome some short-term soldering problems. Such adjustments may cause bigger problems! Instead, the most suitable operating conditions should be found from actual operations and records.
The assembly of PCB is difficult and also requires attention to safety issues. If you are still not very clear about the PCB assembly after reading the above steps, you can contact us for related solutions. We not only provide various information about PCB but also produce high-quality PCB products.
As a professional PCB production manufacturer, we use high-quality materials, exquisite printing technology, and exquisite production technology, and are committed to producing high-quality PCB. If you want to know about our products, please contact us immediately!