1. Preferably crimp and surface mount components
Surface assembly parts and crimping parts, with good technology.
With the development of component packaging technology, most components can be purchased in the packaging category suitable for reflow soldering, including plug-in components that can adopt through hole reflow soldering. If the design can realize complete surface mounting, the installation efficiency and quality will be greatly improved.
Crimping components are mainly multi pin connectors. This packaging also has good manufacturability and connection reliability, which is also the preferred category.
2. Taking the pcba mounting surface as the object, consider the packing proportion and pin spacing as a whole
Package size and pin spacing are the most important factors affecting the whole PCB process. On the premise of selecting surface mounted components, a group of packages with similar or appropriate technical performance shall be selected to paste a certain thickness of steel screen print onto a PCB with a specific size and installation density. For example, for mobile phone boards, the selected packaging is suitable for printing with 0.1mm thick steel mesh solder paste.
3. Shorten the process path
The shorter the process route, the higher the production efficiency and the more reliable the quality. The optimal design of the process path is as follows:
Single side reflow welding;
Double side reflow welding;
Double side reflow+wave soldering;
Double side reflow+selective wave soldering;
Double side reflow welding+manual welding.
4. Optimize component design
The layout design of main components is mainly related to the component layout direction and spacing layout. The arrangement of components must meet the requirements of the welding process. Scientific and reasonable design can reduce the use of incorrect welding tools and joints, and optimize the design of steel mesh.
5. Consider the design of welding pad, welding resistance and steel mesh window
The design of pad, solder mask and steel mesh window determines the actual distribution of solder paste and the process of solder joint formation. It is very important to coordinate the design of welding pad, welding resistance and steel mesh to improve the passing speed of welding.
6. Focus on new packaging
The so-called new packages do not completely refer to new packages on the market, but refer to that your own company has no experience in using these packages. For new package import, small batch validation must be performed. Just because others can use it does not mean that it can also be used. On the premise of using it, we should understand the characteristics of the process and the scope of problems, and master the countermeasures.
7. Focus on BGA, chip capacitor and crystal oscillator
BGA, chip capacitor and crystal oscillator are typical stress sensitive components. PCB bending and deformation in welding, assembly, workshop rotation, transportation, use and other links should be avoided as far as possible.
8. Study cases to improve design standards

Manufacturing design rules are derived from production practices. It is very important to improve the design for manufacturability to optimize and perfect the design rules according to the continuous occurrence of poor assembly or failure.
When designing PCBA boards, engineers should reduce costs and improve assembly quality on the premise of meeting the requirements of overall mechanical and electrical performance, mechanical structure and reliability. What problems should be paid attention to in the manufacturability design of PCBA board? Share 15 points for attention.
1. Minimize the number of PCB layers. If you can use a single panel, you don't need a double-sided board, and if you can use a double-sided board, you don't need a multi-layer board, so as to minimize PCB processing costs.
2. The reflow welding process shall be adopted as far as possible, because reflow welding has more advantages than wave soldering.
3. The pcb assembly process shall be minimized and the cleaning free process shall be adopted as far as possible.
4. Whether it meets the requirements of SMT process and equipment for pcb design.
5. Whether the shape and size of the Pcb are correct, and whether the panel assembly process is considered for the small-sized pcb.
6. Check whether the design of clamping edge and locating hole is correct.
7. Whether the locating hole and non grounding mounting hole are marked with non-metallization.
8. Whether the Mark pattern and its position meet the requirements, and whether 1~1.5mm anti solder area is reserved around it.
9. Whether the requirements for environmental protection have been considered.
10. Whether the selection of substrate materials, components and their packaging meet the requirements.
11. Whether pcb pad structure (shape, size, spacing) conforms to DFM specification.
12. Whether the width, shape and spacing of the lead wire and the connection between the lead wire and the pad meet the requirements.
13. Whether the overall layout of components and the minimum spacing between components meet the requirements; Whether the repair size is considered around large components, and whether the polarity arrangement direction of components is consistent as far as possible.
14. Whether the hole diameter and pad design of plug-in components meet the DFM specification; Whether the distance between adjacent plug-in components is conducive to manual plug-in operation.
15. Whether the solder mask and wire mesh are correct, and whether the component polarity and IC pin are marked.