The common design of the half -lid and half -dew design, and other large designs -PCB foundry, how can you choose you know?

The common design of the half -lid and half -dew design, and other large designs -PCB foundry, how can you choose you know?

Semi -lid and half -dew design:

As the name implies, there is a part of the pad, which is covered with welding ink, and the other part is not covered.

This design will not be adopted under normal circumstances, but if the pads are large and the welding windows are large, the impact will be smaller and the adoption is not harmful, but if it is a smaller pad Window has a large impact. The most common problem is the deformation of pads.

However, this design is difficult to avoid and cannot be adopted. The PCB foundry can only adopt the method of local difference compensation to optimize, but it cannot ensure that it is completely resolved. Therefore, if this situation is encountered, the actual use of PCB in the actual production of PCB should prevail.

Let's talk about the big design.

Waiting for large design, that is, the size of the pads is as large as the size of the weld opening window.

But usually, experienced designers will think that this is a wrong design.

(Note: In the design information sent by my friends, there are large designs such as pads, so there is no design drawing and simulation map)

why?

—— From the perspective of design, this is not a problem, but in the actual production process, the large design is almost impossible to produce, which causes problems. Therefore, under normal circumstances, experienced designers will choose to avoid this problem.

So why, this design can hardly be produced?

——This need to introduce the problem of tolerances of the pad -related process in the PCB production process.

During the design of Layout, because of the limitations of their own knowledge, the designer is often difficult to design the design information in each tolerance of actual production when designing. These tolerances are real, and it will affect the final finished product.

If the PCB's pads are designed as a large design, then most of the produced pads will be as follows -welded ink will definitely cover the pad on one side, resulting in the actual available area of the pads, which can be reduced, and then right to right, then right to right. Subsequent PCBA production causes trouble, such as virtual welding.

Therefore, if the two articles are comprehensive, if the pad can be designed to cover PAD or exposed PAD, it is best. If the conditions are not allowed, it is designed to be half -lid and half dew, and reminds the PCB foundry for local compensation and optimization. No need to design as a big.

OneSeine Technology is committed to providing customers with high -reliable multi -layer board manufacturing services, focusing on PCB research and development, manufacturing, its own environmental protection qualifications, and providing customers with high -reliability and short -term interchange.