Use the right design rules

Ensure that your design rules apply to both blind and buried holes to avoid any problems during manufacturing or testing, such as short circuits or poor solder joints due to incorrect soldering or excessive paste residue around through holes that have been soldered in a non-optimal manner.

Use blind or buried holes only for signal routing

Blind burials are usually used for signal routing; However, they can also be used for power lines, reference layers, ground layers, etc. If you are using blind or buried holes for power or grounding, be sure to follow the correct impedance guidelines for each layer to keep the appropriate current flowing through these layer planes (i.e., use wide pads on the top layer to minimize inductance).

Avoid blind holes and buried holes in areas of high thermal expansion

The coefficient of thermal expansion varies from material to material, and one layer on a multilayer (MLB) is different from another. Therefore, it is important to avoid placing blind and buried holes in areas with high thermal expansion or high temperature cycles, as these conditions may cause unnecessary stress in these areas that can lead to cracking or other problems later in the life of the product.

Avoid critical path

It is important not to place too many blind or buried holes in the critical path on the board. This will increase the possibility of interlayer short circuit and significantly reduce the yield.

Minimum length

The longer the length of the blind or buried holes, the higher the risk of damage from interlayer short circuits or from poor wiring during assembly or excessive trimming of the copper thread due to lack of clearance. Always minimize the length of blind and buried holes to reduce this risk.

Final judgment

HDI blind hole PCBS are becoming the new standard in the electronics industry and there is no shortage of information if you want to make one. However, many guidelines ignore the blind and buried holes required in most designs, which can easily lead to poor board design. We hope our guide has been helpful to you and brings your HDI PCB project closer to completion. If you are interested in learning more about HDI blind hole PCBS and the different types of through-holes, please check out Towers Electronics.

service

After customers complete their orders, the service is closely related to how they really feel. Compared to "products and features", this project is difficult to implement. The services provided by PCB factories mainly include the following aspects:

1) Delivery time

The delivery time of pcb board assembly can be investigated from the following aspects: whether timely delivery time can be provided; Whether the delivery time meets your company's requirements; Tracking service; Some manufacturers even offer you tracking services so they know where your products are going. Usually, well-known PCB suppliers or assembly suppliers work closely with the major Courier companies.

2) Responsiveness

Tao Fang Electronics represents the company's response to customer demands. You can simply study from the following perspectives: Can they respond to new orders quickly? Can they respond to your email with full details within 24 hours? • Can they provide practical solutions in an emergency? Can they expand their manufacturing capacity when you have a rush order? How quick are they to respond when projects change before or during production?

However, responsiveness does not equal responsiveness. Understandably, salespeople know little about a company's manufacturing capabilities, especially when you're looking for technical advice and confirmation. If you encounter a salesperson who tells you that he or she can't tell you until you get a definitive answer from a company technician, you can simply ask to discuss the issues with the technician. Saves time and helps avoid any unnecessary errors during mail transfer.

equipment

Advanced technology can only be fully developed when it is applied to the latest equipment. In the manufacture and assembly of PCBS, the leading equipment and its required specifications include: solder paste printing accuracy. Is it possible to print tiny components like 01005 and CSP, and what type of template is required? SPI (solder paste detection) and other solder paste thickness detector; SMT pcb assembly pick and place machines are accurate in their ability to align microparts (e.g. 01005 and CSP); X-ray inspector. General SMT pcb assembly plant X-ray detection equipment is 2D, suitable for short-cut detection and vacancy; AOI (Automatic Optical detection); ICT devices (Agilent 3070, GenRad, TR5000).

Component procurement

Component procurement is an important part of the services provided by PCB assemblers, so it is important to study component procurement capabilities, including: whether they have established relationships with leading global component distributors; Whether the components are qualified; Whether they accept components from customers; Whether they are storing excess components for your future projects.