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How Do 8-Layer PCBs Revolutionize Circuit Design?

Designing an 8-layer PCB requires specific decisions to ensure high performance, durability and adherence to client specifications. These components have four signal layers and four plane layers. People often choose them because their applications need high-density circuits for high-performance results. These PCBs also provide expanded capacities compared to their counterparts. What should electronics designers do when creating these products for innovative products and needs?

8-Layer PCB

Firstly, they must account for how these PCBs work well for high-density, compact applications, making them popular choices in portable electronics or other small-form-factor products. Additionally, the multilayer structure promotes stable power delivery, which can reduce overheating when designers use appropriate mitigation measures.

Pay Attention to Signal Routing Specifics

A common complication with PCB design arises when people have too many signals routed in small spaces. However, a potential and increasingly popular workaround is to use cloud-based design tools to test specific iterations before committing to prototyping them.

Many such products have built-in collaboration tools to accelerate idea-sharing and productivity across time zones and geographic locations. Users can also communicate with each other by using project management features, such as checklists, tasks and status updates. That information keeps everyone on the same page, making it easier for the responsible parties to provide necessary details and prevent slowdowns that risk compromising the design deadline.

One product uses artificial intelligence to let people design five times faster than they could without the technology. Automated placement features allow making choices in minutes that formerly took days. Some platforms also enable multiple users to simultaneously work on designs, speeding workflows and shortening approval time frames.

When planning routing, you must also decide on the return path. Aim to give the signal the shortest return path and check that it will not interfere with other components. Using specialized software and other digital tools makes it much easier to take a trial-and-error approach to routing.

Modern design tools increasingly include automated features meant to save time. However, designers must be careful not to become overly reliant on them. Even the most advanced tools can still make impractical suggestions, emphasizing the necessity of applying common sense and best practice knowledge rather than quickly assuming the automated suggestions are the best options.

Test Multiple Possibilities With Simulation Tools

Successful 8-layer PCB design decisions happen when professionals follow best practices and know when to test new ideas. With the availability of digital twins, that has become significantly easier. Manufacturers, designers and other industry participants use them to develop unique and scalable options for mass production or individual clients.

Some simulation tools for PCB designers develop sophisticated stackups. As people experiment with different sizes and varieties, they can make well-informed 8-layer PCB choices. Impedance analysis calculators also reduce manual determinations or best assumptions. Additionally, users can enter target impedances to generate suggested trace widths.

Another product uses artificial intelligence to significantly speed up layout design. Outsourcing that task can cost up to $10 per pin and some boards have hundreds of pins. However, using AI to accelerate the process with an in-house team is an excellent way to save time and cut unnecessary expenses.

Consider using these tools to guide client discussions, especially when customers ask for specifics that are unlikely to be feasible for specific applications. The automotive, aerospace and electronics industries are among those most likely to use 8-layer PCB designs because of their suitability and how the multilayer structure supports requirements such as high reliability and signal processing capabilities.

You could also use simulation tools to help clients visualize options. The simulated images and designs help break down some of the barriers that may exist between clients with little or no technical expertise and designers who live and breathe high-tech concepts.

Accommodate Temperature-Related Needs

Estimates suggest that improper temperature management can shorten components’ residual life span by 50%, emphasizing the need for designers to always investigate appropriate heat mitigation measures. Similarly, they must understand the knock-on effects of excessive temperatures. They can damage a PCB’s solder pads and cause copper delamination, necessitating repairs.

Designers should begin by determining the components most likely to generate high levels of heat and then explore suitable mitigation strategies. For example, those associated with the most power should be away from the PCB’s edges and corners unless there is a heat sink for thermal management. Distributing them throughout the component prevents heat concentration.

Additionally, using flame-retardant substrates and choosing thermally optimized layouts are some fundamental steps to follow. Eight-layer PCB designs are also better at distributing heat than some counterparts, but that does not mean professionals can ignore best practices for keeping the temperature manageable. Alternatively, filling thermal vias with conductive epoxy resin and covering them with copper turns them into heat pipes to transfer the warmth away from the affected areas and distribute it.

Thermal coatings are other viable possibilities. One company’s solution simultaneously increases heat dissipation efficiency by more than 10% while decreasing the temperature of memory modules containing the PCBs.

Since an 8-layer PCB offers more design flexibility than its counterparts, designers should strongly consider using thermal mapping tools that show which areas have the highest temperatures and experiment with moving the current heat mitigation measures or changing their types.

Use 8-Layer PCB Design Principles to Guide the Outcome

In addition to applying these tips, always abide by well-established design principles and resist trying new things or going beyond typical circuit design best practices. Such experimental approaches have value in research labs and other experimental settings, but best practices should be at the forefront of all client-related projects.

Treat them as foundations that can shape innovative ideas, especially if the project timeline supports trial and error. Investigate ways to maintain the aspects necessary for good performance — such as thermal management and appropriate routing — while using design platforms and other tools to develop new iterations that take advantage of specific 8-layer PCB characteristics to harness increased capabilities.

Keep records of which design choices worked well for certain projects and which were less suitable than first envisioned. This will enable you to save time later on different, similar efforts. Referring to these also helps you cultivate continuous improvement and growth, supporting your company and clients.

Emily Newton is the Editor-in-Chief of Revolutionized Magazine. She has over six years experience writing articles for the tech and industrial sectors. Subscribe to the Revolutionized newsletter for more content from Emily at https://revolutionized.com/subscribe/