hdi pcb manufacturers: Best Guide for Perfect HDI PCB 2022

Unlike many other industrial products, whose quality control is often done by sampling, a batch of print circuit boards needs to go through the final quality control processes on 100% of it. For this, you need professional hdi pcb manufacturers.

The various delicate and high-precision physical and chemical processes. Through it a plate passes during its manufacture generate a very high possibility of process deviations.

Why do you need professional hdi pcb manufacturers?

Therefore, in addition to prior quality control, it is important to hire professional hdi pcb manufacturers. This begins to occur from the moment the raw materials receive and also takes place during the execution of each process, it is extremely important that there is a strict final quality control.

Quality control during the process

Hole sizing, crease depth, internal cutouts and external contours check collectively. Moreover, In the event of any anomaly, this process starts to have an individualized check on each plate. In situations that require even more exact precision, three-dimensional analysis equipment is common.

Mechanical dimensions o hdi pcb

• Visual aspects of the positioning of the circuit images
• the anti-weld mask and the component legend
• the perfection of the surface finish

It can be it tin, copper, varnish, etc., check on each part, one by one, with powerful adjustable magnification lenses and special lighting. You can contact professional hdi pcb manufacturers.

Visual pre-inspection

The constant miniaturization of electronics has made the use of human vision alone in inspection processes less and less effective. In addition, human operators, no matter how well they have training and experience they are.

This will always be susceptible to other factors, such as:

• loss of concentration due to external factors
• eye strain
• necessary breaks

It will always impact the quality and productivity of the process.

Therefore, depending on the complexity of the batch, all analysis must carry out by hdi pcb manufacturers. This process comes on comparison, where a pre-approved board from the batch is common.

How to build hdi pcb image?

Golden board image stores in the software memory as a reference. Then, the points of the plate being tested will compare to the stored image, through an automatic scan that uses high-intensity light sources. Moreover, it comes with high definition cameras. It captures the image of the plate test and superimposes it on the image stores in the software.

AOI

Thus, it segregates plates with eventual defects, indicating the exact location of these defects in a few seconds.

Despite all the advances in this process with increasingly technological sensors, lighting and cameras, there is still no guarantee of the perfect electrical functioning of the board. This obtains through electrical test equipment under hdi pcb manufacturers. This equipment is also constantly evolving and following the miniaturization of the boards.

For large batches, priority gives to the use of equipment that works with the use of test gigs. These are good specifically for that board. These gigs have interconnected probes at the same locations as each pad, pad, or board contact. On both sides and in the same way, a golden board is common.

How to get best hdi pcb?

This will serve for the equipment’s software to perform the “learning” of all the connections on the board. After this learning process, the boards to test introduce into the equipment.

This compresses the board between the “needles” of the jig, on both sides, electrically certifying the continuity and dimensioning of the entire circuit. Thus, any possible electrical anomaly regarding the golden board or the board’s software is acknowledged.

Electrical testing with dedicated test jib

Due to the high cost of construction of the jigs, this process may be unfeasible for batches of small quantities of boards. The use of hdi pcb manufacturers point-to-point testing equipment is more important. Moreover, the pairs of golden needles of this equipment go through all the contacts on the board, one by one, at the beginning and end of each connection.

At an excellent speed, they base on the circuit’s software, to verify that all connections are compatible with the same. This process is not suitable for batches of large quantities of plates and with many contacts to test, because despite the high speed of the test needles, a single board can take many minutes to fully test.

Point-to-point electrical test

The efficiency of both processes is really high. This ensures reliability levels very close to 100%. Combining these testing and inspection processes to choose the best option based on board complexity and lot size should consider the best cost-benefit ratio.

Thus, total reliability in the quality of the boards seeks without increasing their cost, especially in cases of less complex boards. You need to rely on professional hdi pcb manufacturers. On the other hand, there are boards in which it will never be possible to guarantee perfect quality without the specific application of one of these processes.

The determination of tolerances in the hole diameters, in a printed circuit board, must take into account some factors, which make it difficult to fully control these measures in several manufacturing processes of the board.

How to adjust gerber files?

The impossibilities of meeting centesimal tolerances specifications already start with the availability of existing tools on the market. Tungsten carbide drill bits, common in the cnc drilling process, are only available in 0.05mm intervals. That is, once the diameter determined in the gerber file is different from this range of 5 hundredths of a millimeter, it will need to round.

Tungsten carbide drill bits

Drills with intermediate measurements at these intervals are factual.  And even these drills with a nominal interval of 0.05mm; also have their dimensional tolerance already informed by the drill manufacturer. This tolerance can be from 0.003mm to 0.01mm, according to its diameter.

In addition, the friction generated during the penetration of the drill into the laminate, generates wear on the drill and, as this drill performs a high number of insertions in the plate, it will be reducing its cutting surface and also its diameter. Therefore, all drills undergo a limited amount of regrinding, being discarded after reaching this limit.

Summary hdi pcb manufacturers

Are you in doubt about which process is the most suitable for the best final result of your print circuit boards? Our hdi pcb manufacturers is always available to evaluate and recommend the best option for you.