OSM (Open Standard Module) defines one of the first standards for directly solderable and scalable embedded computer modules and marks a milestone in the miniaturization of modular COM/carrier designs, replacing credit card-sized modules with postage stamp-sized ones.
The specification aims to standardise the footprint and interface set of low-power and ultra-low-power application processors based on MCU32, ARM and x86 architectures across different sockets, manufacturers and architectures. Target applications of the new module standard include IoT-connected embedded, IoT, and edge systems that run open-source operating systems and are used in harsh industrial environments.
“OSM modules give ODMs and OEMs an ultra-miniature form factor with attractive pricing and high scalability. Since the modules are application-ready and come with all necessary software drivers and BSPs, and since the specification is open source – both in terms of the hardware and software – we expect them to be of high interest for the globally active embedded and IoT system development community,” explains Martin Unverdorben, Chairman of the SGET STD.05 Standard Development Team, which started work in October 2019.
OSM modules look to simplify and accelerate the design-in of processors. At the same time, applications become processor-agnostic, which makes them scalable and future-proof. The OSM specification also offers an extra level of ruggedness thanks to the BGA design and automated surface mount technology (SMT), which can further reduce production costs in series production.
All OSM modules are published and licensed under the Creative Commons Plus (CC+) dual license. This allows an open licensing model, such as the Creative Commons Attribution-ShareAlike license (CC B-SA 4.0) for a defined set of materials, components and software, and a commercial license for everything not included in this set. This ensures that development data will be publicly available. However, t is still possible to license the Intellectual Properties (IP) of a carrier board design commercially without violating the open source idea.
The new OSM specification expands the portfolio of SGET module specifications with solderable BGA mini modules that are significantly smaller than previously available modules: Even the largest OSM module, measuring 45x45mm, is 28% smaller than the µQseven (40x70mm), a standard also hosted by SGET, and 51% smaller than SMARC (82x50mm).
Other module sizes in the new OSM specification are even smaller: OSM Size-0 (Zero) has the smallest footprint with 188 BGA pins on 30x15mm. OSM Size-S (Small) measures 30x30mm with 332 pins, OSM Size-M (Medium) offers 476 pins on 30x45mm, and Size-L (Large) measures 45x45mm and comes with 662 BGA pins. SMARC, by comparison, specifies 314 pins and Qseven 230. This means that BGA design makes it possible to implement significantly more interfaces on a smaller footprint – which constitutes another unique advantage of the new OSM standard.
The interfaces vary in type and design depending on the size of the OSM modules. In maximum configurations, OSM modules provide all functions that make up an open programmable embedded, IoT or edge system, including GUI. Modules from Size-S upwards offer video interfaces for up to 1x RGB and 4-channel DSI. Size-M modules can additionally support 2x eDP/eDP++, and Size-L adds 1x LVDS interface for graphics. All modules from Size-S upwards further offer a 4-channel Camera Serial Interface (CSI).
Size-L modules provide up to 10 PCIe lanes for quick connection of peripherals; Size-M offers 2x PCIe x1, and Size-S 1x PCIe x1. In view of their extremely miniaturized footprint, Size-0 modules do not feature any of the I/Os mentioned so far, but offer all the interfaces listed in the following.
The OSM specification provisions up to 5x Ethernet for system-to-system communication. In addition, all modules have what is called a communication area, providing 18 pins for antenna signals for wireless communication or the integration of field buses. There are up to 4x USB 2.0 or 2x USB 3.0 (only in Size-L), up to 2x CAN, and 4x UART. Flash storage media can be connected via UFS. Up to 19 pins are further available for manufacturer-specific signals.
To complete the feature set, there are up to 39 GPIOs, SPI, I2C, I2S, SDIO and 2x analogue inputs. As a safeguard for the future and to ensure that any future expansions are backward compatible, up to 58 pins are reserved for future purposes.
