In the electronics manufacturing industry, surface mount technology (SMT) is one of the core technologies of modern electronic assembly, and its high efficiency and precision characteristics have greatly promoted the miniaturization, lightweight and high performance of electronic products. Different types of PCB (printed circuit board) boards show different characteristics, advantages and process requirements in the SMT chip processing process due to their unique structure and design. This article will explain the characteristics and advantages of different types of PCB boards in SMT chip processing.
1. Single-sided side
Single-sided is the most basic type of PCB with only one conductive pattern layer, typically used for simple circuits. In SMT chip processing, the advantage of single-sided board is its simple structure, clear chip path, and easy layout and wiring. However, due to the limitations of the single-layer design, the density and complexity of the components are low. During processing, it is necessary to pay attention to the rationality of the layout between the components, avoid pin interference, and control the soldering temperature to prevent the deformation of the substrate.
2. Double-sided panel
The double-sided panel has two conductive pattern layers connected by guide holes, increasing the complexity of the circuit and the density of components. In SMT processing, double-sided panels are able to carry more components, increasing the integration of the product. During machining, it is necessary to precisely control the manufacturing quality of the guide hole to ensure the reliability of the electrical connection. In addition, when double-sided mounting, it is necessary to reasonably plan the height of the components to avoid occlusion or interference, and at the same time use appropriate fixtures and process parameters to ensure the accuracy and stability of the mounting.
3. Multi-layer board (multi-panel)
The multilayer board is composed of multiple layers of conductive pattern layers and insulating dielectric layers that are alternately superimposed, enabling highly complex circuit designs through inner layer interconnections. In SMT processing, multilayer boards are the first choice for high-end electronic products due to their high integration, low electromagnetic interference, and excellent signal integrity. The processing challenges are the precise alignment of the inner lines, the control of bubbles during the lamination process, and the reliability of the interconnection between the multiple layers. In addition, multilayer boards have extremely high requirements for the processing environment and equipment accuracy, and require advanced automation equipment and precision processing technology.
4. Flexible circuit board (FPC)
Due to its bendable and foldable characteristics, FPCs are widely used in applications that require a high degree of flexibility and space constraints. In SMT processing, the flexibility of FPC puts forward special requirements for the placement process, such as using flexible placement heads, adjusting placement pressure and speed, etc. At the same time, the temperature resistance of FPC is low, and the welding temperature and time need to be strictly controlled to prevent deformation or damage to the substrate. In addition, FPCs have a high wiring density and require extremely high placement accuracy and stability.
5、软硬结合板（Rigid-Flex）
Rigid-flex boards combine the advantages of rigid and flexible boards, with the stability and high integration of rigid parts and the flexibility and bendability of flexible parts. In SMT processing, rigid-flex boards need to pay special attention to the transition area between the rigid and flexible regions to ensure the compatibility and stability of the two in the placement process. At the same time, it is also necessary to consider the difference in the coefficient of thermal expansion of the material to avoid stress concentration and damage caused by temperature changes.
6、高密度互连板（HDI）
HDI boards are key components of high-end electronic products such as smartphones and tablets to achieve high-density and high-precision circuit design through microvia, blind and buried via technologies. In SMT processing, HDI boards have extremely high requirements for machining accuracy and process control, such as the accuracy of laser drilling, the uniformity of electroplating and filling, and the flatness of surface treatment. In addition, the compact layout of the components of the HDI board puts forward higher requirements for the positioning accuracy and stability of the placement machine.
In the actual production process, different types of PCB boards have their own characteristics and challenges in SMT chip processing. Understanding and mastering these characteristics is of great significance to improve production efficiency and ensure product quality. With the continuous development of electronic technology, PCB boards and their SMT processing technology will continue to innovate in the future, providing more solid support for the intelligent, networked and green electronic products.
Source: https://www.yunhengzhizao.com/news/jszs/1744.html