PCBA Tech - Selection of packaging and SMT steel mesh production

The benefits of choosing the right package in SMT chip processing

SMT surface mount components are no different in function from plug-in components. The difference lies in the packaging of the components. Surface-mounted packages must withstand high temperatures during soldering, and their components and substrates must have matching coefficients of thermal expansion. These factors must be fully considered in product design.

The main advantages of choosing a suitable SMD processing package are:

1. Effectively save PCB area;

2. Provide better electrical performance;

3. Protect the interior of the components from humidity and other environmental influences;

4. Provide good communication links;

5. Help heat dissipation and provide convenience for transmission and testing.

The selection and design of SMT surface mount components is a key part of the overall product design. The designer determines the electrical performance and function of the components in the system structure and detailed circuit design stage. In the SMT design stage, it should be based on the specific conditions and conditions of the equipment and process. The overall design requirements determine the packaging form and structure of surface mount components.

Surface-mounted solder joints are both mechanical connection points and electrical connection points. A reasonable choice will have a decisive impact on improving PCB design density, productivity, testability and reliability.

Precautions for the production and acceptance of steel mesh in SMT patch processing plant

SMT steel mesh is a special mold in SMT processing. Its main function is to help the deposition of solder paste. The purpose is to transfer an accurate amount of solder paste to an accurate position on the empty PCB. SMT steel mesh plays an important role and affects the paste. The quality of the film processing. Therefore, there are strict standards for the production and acceptance of steel mesh. The following Jingbang SMT processing plant will organize and introduce SMT steel mesh production requirements and acceptance precautions.

1. SMT steel mesh production requirements:

1. According to the relevant documents and materials provided by the Engineering Department, the supplier is required to make steel mesh.

2. The steel mesh needs to be marked with the product model, thickness, production date, etc.

3. The frame size of the steel mesh is required to be 550MM*650MM 370MM*470MM, etc., which are mainly determined according to the structure of the printing machine and the specifications of the product.

4. The thickness of the steel mesh (generally 0.18MM-0.2MMM for squeegee, 0.1MM-0.15MM for tinning).

5. The opening method and size of the steel mesh (the anti-tin bead is generally V-shaped, U-shaped, concave, etc., depending on the type of each component.)

6. The direction of the board and the placement machine should be unified.

2. Precautions for acceptance of SMT steel mesh:

1. Check whether the method and size of the steel mesh opening meet the requirements.

2. Check whether the thickness of the steel mesh meets the product requirements.

3. Check whether the frame size of the steel mesh is correct.

4. Check whether the marking of the steel mesh is complete.

5. Check whether the flatness of the steel mesh is level.

6. Check whether the tension of the steel mesh is good.

7. Check whether the position and number of openings in the steel mesh are consistent with the GERBER file.