Printed circuit board design can involve the connection of modules having different functionality. You can create simple designs without the impact of a PCB layout on the PCB operation. Also, a simple design might not require you to consider the relationship between several functional blocks on your circuit board.
However, more complex PCB designs require you to consider a lot of factors. You will need to not only consider the overview of your board, but also consider other parameters. The modular PCB design is implicitly integrated when designing circuit boards for various applications. This design methodology is beneficial to embedded systems, mixed signal systems, and multi-board systems. Other circuit boards with high functionality can as well benefit from this design.
What is a Modular PCB?
A modular PCB is a piece of hardware that features a particular functionality. This circuit can be connected as part of other circuits. A modular PCB is a circuit separated into modules rather than one complete setup. This refers to splitting a complete printed circuit boards into several circuit. Connectors or via cables are used in connecting these several circuits to each other.
The modular PCB design is not a new concept in electronics design. A good example is the assembly of computers. A modular PCB for computer comprises single motherboard having slots for sound cards and graphics cards. Platforms such as BeagleBoard and Arduino highlight the modular design trend ans as such it enables the connection of independent modules in an ecosystem.
Furthermore, modular PCB design provides better flexibility for designers to perform some tasks.
What is a Modular PCB Design?
The modular PCB design is integrated when designing circuit boards for various applications. This design methodology is beneficial to embedded systems, mixed signal systems, and multi-board systems. Other circuit boards with high functionality can as well benefit from this design.
You will realize some design tools can’t be used due to inconsistent data formats and lack of unification. However, some design software are upgrading their tools to meet the demands of modular PCB design. Also, PCB designers can have full access to these design software packages. There are some unified PCB design software packages that feature set of tools for modular PCB design.
In those days, PCB design involved treating each part of an electronic system separately. The design process barely considered the connections between various parts of the systems except when complex boards are being created.
However, the electronics industry is constantly evolving as electronics are becoming connected and smarter. Consumers now demand improved functionality. Therefore, PCB designers are seeking for ways to embed this functionally in a device.
Modular PCB design is one such approach designers are now integrating. This design methodology takes an electronic system’s hierarchical view. Also, it is a multi-board design methodology which enables the separation of functionality on various boards.
Modular PCB Design Process
When we talk about a modular design, you might need to view your device as regards separate functionality. The easiest way is starting with your device’s functional block diagram. Designers will need to understand how different parts of their device work to offer the functionality they need. Also, desired outputs and inputs will need to be considered in this case.
Furthermore, you will have to consider the functional block diagram as part of your design process when a device comprises central processing. Therefore, it is crucial to make some changes to the design when you begin the PCB layout process. The majority of PCB designers don’t consider the interaction between functional blocks in their device before they start laying out their circuit board.
Designers may have to develop better block diagrams that reveal the functionality of each part of the device. This means that a hierarchical approach is needed in designing the key features of the board.
How to Use Schematics for a Modular PCB Design
The first step in a modular PCB design is to create schematics. As regards modular design, you can create connections between PCB components within every functional block in the diagram. With this, you can begin the modular PCB design.
The hierarchical schematic editor can help in connecting schematics. This tool is designed for PCB design. Therefore, this enables you to define the interactions between several schematics. Also, this can help you remain organized all through the design process and enable you focus in one part of the design.
Furthermore, you can connect several schematics within higher level parent schematic. In several systems, you will reintegrate some parts of your PCB design. In such a case, you don’t need to redesign parts of your boards in various schematics. Modular PCB design enables you to reintegrate parts of your design in various schematics. Therefore, you don’t need to rearrange the same components several times.
You can transition the board layout stage once the relationships between schematics have been defined and the functional block diagram has been transformed in hierarchical schematics. Furthermore, it is necessary to capture the schematics on a new board. You can now begin the process of arranging the components once the connections and components have been captured.
The Layout Phase of Modular PCB Design
After importing the schematics as the layout, you can now arrange components on the board. Using the appropriate schematic capture tool will help in ensuring your organization remains defined in the schematic. Also, it will reveal the connections between components. Some circuit boards will have their functionalities divided into various parts of the board. For instance, you should design the mixed-signal systems in such a way that the analog and digital areas create functional blocks.
In such a case, every block will need separation in its areas. This will help ensure signal integrity. After you add more functionality like wireless communication or Wi-Fi module, the layout should be in its functional block. The designer will need to assign every type of functionality to their area of circuit board in to ensure signal integrity.
Modular PCB Design Software
Modular PCB design is a process that requires some additional tasks. Therefore, the software integrated for this design needs to feature some functions other design packages don’t offer. The modular PCB design software must feature multi-channel schematic editing tools. PCB designers will be more productive when the software also features a schematic editor and a schematic capture tool.
Another crucial feature a modular PCB design software should have is component management. Designers will have to reuse several components in various locations all through the entire board when carrying out multichannel design. This means a component library that comprises your design features will be needed.
The ability to integrate these features in only one interface enables easy generation of layouts and start component arrangement all through the system. Also, the layout editor will enable the grouping of components, which makes component rearrangement easy. With this, you can correct any layout errors and stay organized before you commence with manufacturing.
Efficient PCB design software will offer you a working environment that enables you have access to sophisticated tools. There are some features that enable you achieve an excellent modular design. A crucial aspect of modular PCB design is simulation. Simulation helps you confirm some crucial aspect of EMI suppression and crosstalk.
An integrated design software enables the direct transfer of your design data to your simulation tools. Also, you can restrict your simulations to some particular functional blocks that are within your system. A crucial aspect of modular design is ensuring that every functional block performs well. Therefore, an efficient design software package will help you achieve all this.
Why is a Modular PCB needed?
When creating a circuit board for a whole circuit, there is always less stress. However, there are situations where you might need to integrate a modular approach. A modular approach could be a better choice in such cases. So, why is a modular PCB important?
Space constraints
When manufacturing a circuit board, there is a limited number of components you can mount on the board. For instance, when designing products that feature limited space, you might not be able to integrate a single PCB design since it may not be ideal for the enclosure. Therefore, a modular PCB design can be a better option. This is because sharing the design in different modules helps in ensuring that these modules fit well.
With the increasing development in the miniaturization of electronic products, modular PCB has become a popular concept in the industry. This concept is something a designer would need to integrate.
Reusability
In some electronic products, there are some parts that can be replicated. For instance, a micrcontroller module can work for an alarm controller than a humidity logger. Therefore, you can easily reintegrate similar module for various products. This helps in saving cost for any redesign and as such offers a low cost-per-unit when more of this same module is produced.
Ease of upgrades
Some electronic components are experiencing more upgrade than others. For instance, network ICs and microcontrollers experience upgrade each 2-3 years. Therefore, some electronic components can become obsolete during a product’s lifecycle. However, keeping components that need upgrade on the same module will require you to rework some part of the board when you need an upgrade.
Troubleshooting and testing
The process of troubleshooting and testing can be very difficult one, especially when there are many components on a circuit board. When testing a prototype, there are some unknown factors that determine if the design is very functional.
Developing a modular board restricts testing to particular parts without the need to break traces. Furthermore, maintenance and troubleshooting are much easier to perform since you can easily detect and replace faulty modules.
Techniques in Modular PCB Design
There are a few techniques that will help in achieving a modular PCB design.
Dividing the parts
It is important to divide the parts of modules you are creating and as well group the components. Most times, you can group an embedded system into communication, power, microcontroller, and I/O.
Scalability
When working on a modular PCB, it is crucial to consider the possible design for scalability. For instance, you can make use of part of the I/O pins on a microcontroller and then route the remaining pins for future use.
Interconnection
You need to bring the modules together to make them whole. In some cases, you need to know if the modules need stacking with connectors or need to be connected with cables. Also, board-to-board connectors are usually needed to connect modules that feature high-speed signals.
Mechanical accuracy
It can be very frustrating when you realize that the modules don’t align and as such can fit together. Also, modules can go beyond the size of the enclosure on the Z-axis. Therefore, it is very crucial to use the right coordinates when working on a modular PCB design, especially when there are stackable connectors involved.
The modular PCB design is easier when you integrate software like Cadence Allegro that uses ECAD-MCAD to check any mechanical constraints.
Applications for Modular PCB Design
There is a wide array of applications that benefits from the modular PCB design. One application of modular design approach is the computer architecture. With the advancement in consumer products which includes connectivity and the integration of sophisticated functionality, a modular design approach will help in achieving a successful design for these products.
Electronic products or gadgets like smartphones, wearable devices, home automation systems, and entertainment systems integrate modular PCB design approach. Most of these devices integrate multi-board systems which need advanced design tools to build a functional design.
Modular PCB design software should provide sophisticated functionalities, but it shouldn’t make the design process difficult. The modular design process can become easier and faster when the required tools are in the software. A good design software for modular design should feature tools needed for building comprehensive systems.
Conclusion
Modular PCB design entails the visualization of your design in a new dimension. This design methodology is beneficial to embedded systems, mixed signal systems, and multi-board systems. Modular PCB design is a process that requires some additional tasks. The software integrated for this design needs to feature some functions other design packages don’t offer.
