Modular Electronics Design for Embedded SystemsBy ZM Peterson • Nov 22, 2019
We love modular electronics design, modular software design, and even modular IC design around here (yes, modular IC design is now a thing!). Modular electronics design has gained a lot of momentum in the last decade, especially in the world of embedded systems.
One great example is in computer-on-module (COM) boards, development boards like Arduino, and a host of shield boards that can be added to an existing hardware platform with standard interfaces (I2C, SPI, GPIO, UART, etc.). The goal in modular electronics design is to break down a generic system into several independent parts called modules. These are then used together to define the functionality of a device. They are independent in the sense that, a module doesn’t depend on another module to function and will only depend on the base platform. Modules usually are linked together using standardized interfaces, allowing a multitude of new systems to be customized for unique applications.
What is Modular Electronics Design?
If modular design sounds foreign, it is actually a simple concept. In essence, modular electronics design is all about linking together multiple electronic devices into a single system. This is done by taking advantage of the standardized electrical connections (e.g., PCIe, SATA, I2C, SPI, etc.) that are used in electronic devices. This level of standardization is present at the physical level (in the PCB layout and on the PCB itself) and at the signaling standard level.
Three famous examples of modular electronics design in the embedded world are Raspberry Pi, BeagleBone, and Arduino. Other companies have tried to capitalize on the modular wave and have produced their own modular platforms. Some examples include Seeed Studio, STMicroelectronics, Advantech, and others. What makes these hardware platforms modular is the ability to add peripherals to the board by simply plugging them into a set of headers and referencing them in the firmware. If you look at the Raspberry Pi platform, which is basically a set of single-board computers (SBCs), you’ll find displays, cameras or imaging systems, a range of sensors, motors, and other peripherals available for your new board.
One way to add new components and capabilities to your embedded SBC or a development board is with shield boards. These boards connect to the header pins on your SBC and provide a placeholder for a number of different components. You can also design customized shields for your board. Many shields are stackable, meaning you can combine them on top of your board as you see fit. Shield design for specific applications follows the same principles as PCB design in any other area.
This Raspberry Pi with a shield board is an ideal example of modular electronics design.
As hardware has gone modular, so has the software required to support these products. The open source community has gone a long way towards providing a broad range of software to run modular systems, and to provide data acquisition, processing, and control functions. This brings us to SBC design…
Modular SBC Design with COMs
COMs are a great way to add embedded computing to a custom board. These small modules are the size of RAM sticks and contain all the required hardware to run an operating system and custom software. COMs are designed to be application agnostic, in contrast to a system-on-chip (SoC) or system-on-module (SoM). They typically include all the standardized signaling protocols you need to communicate with a wide range of peripherals, allowing then to be easily adapted to specific applications. The specificity comes from the peripherals you add to the system.
A modular embedded system offers systems designers significant flexibility to adapt to different use scenarios. The baseboard of an SBC can include features like USB connectivity for power and data, an SoC/SoM for , basic WiFi/Bluetooth/LoRaWAN connectivity, HDMI display, an expandable GPIO header, and many other modular components. Other modules can be built to take user or environmental input, such as a display addon, motor controller, GPS/GNSS, cellular modem (3G/4G/5G), sensors (accelerometers, gyroscopes, IMUs), and much more.
6701 COM powered by a Snapdragon 845 processor from our client Inforce Computing.
With this modular approach, embedded system developers will be able to focus on building a compelling application-specific layer and focusing on the high-level hardware and software to make it possible, rather than getting bogged down in the finer points of schematic design and building a PCB layout. The designer can focus on the functionality they need and routing connections on a baseboard, rather than integrating fundamental computing components onto a brand new board.
The Future: Modular System-on-Chip Design
The new design tools from ARM DesignStart bring us to the next level of modular electronics design: modular SoC design and manufacturing. If you’ve ever built a complex system of discrete components and want to pack it into an ASIC or an FPGA, now you can access tools that make this possible. ARM-based processors and SoCs are arguably the best choice for embedded, mobile, or IoT applications.
In the past, designers would have to contract with a major semiconductor design firm or manufacturer, and they would have to order lots of thousands of wafers or spend a considerable amount of money on a small number of chips. With these new design tools, systems designers can focus on linking a number of standardized modules at the wafer level into a single IC. These chips are meant to be application specific, but this allows you to take a system built from discrete components and miniaturize it.
The best part of the modular electronics design revolution is that anyone with a great idea can quickly build a product without needing specialized design knowledge. This also helps innovators get a new product to market quickly and experiment with novel functionality. Standardized modular hardware platforms, baseboard design tools like Geppetto, and DesignStart give embedded systems entrepreneurs and established companies an easy way to quickly build out a new product.
If you’re thinking about taking a modular electronics design approach for your next embedded system, it helps to have an innovative design and marketing firm by your side. We offer cutting-edge PCB and modular design services and digital marketing services for innovative electronics companies, making us the ideal choice to build and market your new product. Contact NWES for a consultation.