Seven Tips for Ensuring Quality in the Main PCB Assembly Process

How to Ensure the Quality of Main PCB Assembly Process?

The PCB Assembly Process starts with the basic unit of the Printed Circuit Board. A PCB can consist of several layers, however, this greatly depends upon the functionality and complexity of the PCB. Every layer of the Printed Board has some important functionality that contributes towards the final PCB functionality.

Before we get down to the tips that would ensure the quality of the Printed Board. We would define the PCB assembling process.

Introduction to the Main PCB Assembly Process

The alternating layers of the Printed Circuit Board are as follows:

Substrate

The substate is responsible for the PCB rigidity. It is the base material.

Copper

Every functional layer of the Printed Circuit Board comes with a conductive copper foil layer. When the manufacturer places the copper, foil lay one side of the Printed board, it becomes a Single-PCB. Whereas, when the copper layer is present on both sides, it comes the Double-sided PCB.

Solder Mask is Important for PCB Assembly

Solder mask is the green color that we see on the Printed Circuit Board. It is present on top of the copper layer. The main purpose of this layer is to ensure that the copper races do not come in contact with other conductive materials.

If they come in contact with other conductive materials, it would lead to a short. In lame man terms, we can say that the solder mask is responsible for keeping every component of the Printed Board in contact.

Silk Screen

The final layer of the Printed Board is the silkscreen layer. It is in white color and the layer is responsible for adding labels to the Board. These labels can either be symbols or characters. Due to these layers, people are able to understand the function of each component on the Printed Board.

The components and the materials of the PCB remain the same across all Printed Boards. Although, it is possible to have different base material. The type of substrate you use would greatly depend upon your product features and requirement.

Three Primary Printed Circuit Boards

Thanks to modern-day sophisticated main PCB assembly processes, we have numerous types of Printed Circuit Boards. However, below we will be discussing the three primary types of Printed Boards.

Rigid Printed Board

The most common Printed Board is the Rigid PCB. Since it is cost-efficient, thus you will find it more common. It has a rigid base that ensures the robustness and sturdiness of the PCB. The Rigid PCB offers a number of the substrate material.

Fiberglass is the most popular one. However, to further decrease the price of the board, you can use material such as phenolics or epoxies.

NOTE: Both Phenolics and Epoxies are less durable in comparison to Fiber Glass.

Metal Core Printed Board

If you are looking for an alternative for the typical fiberglass boards, you can use metal core PCBs. The biggest advantage of these boards is that they are excellent heat dissipaters. Their metal base allows spreading heat in an efficient and effective manner.

Flexible Printed Boards

Flexible Printed Boards become increasingly popular among modern, compact devices. Unlike their rigid counterparts, these boards can fit a number of devices while offering better functionality.

The base material for a Flexible PCB is something like Kapton. It means that it is possible to bend the material.

Factors to Consider to Ensure Main PCB Assembly Process and Product Quality

For effective Electronic Engineers, the designing of Printed Circuit Boards is a regular task. Despite having years of experience, the PCB designer might have some issues. Below, are some effective tips that will help you yield premium quality of Printed Boards.

Board Materials

What is the cornerstone of a Printed Circuit Board? It is the Board Material. It defines the quality and the rigidity of PCB. The non-conductive board material of the PCB would be laminated with the copper layer.

Since the board material is responsible for ensuring the sturdiness and robustness of the PCB, therefore it needs to be of premium quality. You can use glass-reinforced epoxy as the base material. This basically the FR-4 material.

In addition, there are some other flame resistant and affordable materials as well. If you plan to design and develop a high-performance PCB, you should use either a ceramic base or the PTFE. To add more to the strength, the engineers would use some additional fillers as well.

Main PCB Stack-Up

The Printed Board stack-up refers to the PCB’s layers. Due to the Stack-up, the electronic engineer is able to comprehend the needed impedance of every layer. When the engineers have the appropriate estimation of the number of PCB layers, they are able to choose the main PCB assembly process.

Thus, ensuring that they attain the desired result and develop high-quality, fully functional Printed Circuit Boards.

Copper Traces

Copper traces are among the vital components of the Printed Board. While designing the PCB, it is imperative to highlight both the strengths as well as the weakness of these traces.

Part Selection for Main PCB Assembly Process

Even though it is the most tedious process of the Printed Board design process, yet it holds great importance. When you choose the correct part for the PCB, you are able to minimize the errors to a great extent.

Since several components are present in the market, remember the pointers below to choose the correct ones.

Avoid using parts that are not readily available or they are no longer produced.

Also, consider the number of every part you want. In order to buy certain parts, you would have to place mass order. If that is not something you want to do. Look for a better alternative.

Via Types

In order to establish a connection between different components of the Printed Boards, the manufacturers use via. There are different types of vias. The manufacturer uses the one that suits the requirement of the Printed Circuit Board.

For instance, you have Micro, Blind, Through, and similar other vias. However, the critical point to remember here is that an effective, and quality PCB design consists of minimum vias. Adding more vias to the PCB would add unwanted complexity.

Design Rule

After pay attention to the above pointers, it is time for the designer to focus on the design rules of the main PCB Assembly process. Consider things like component placement, budgets, development to market time, layer allocation among others.

Power Integrity and Signals

It is important to focus on the fall and rise of the signal time, characteristics impedance as well as the track lengths and the drive strength. Paying attention to these components ensures the credibility and effectiveness of the Printed Circuit Board.