COM Express is a family of modular, small form factor computer-on-module (COM) specifications that make mid-range edge processing and networking capabilities available to automation, gaming, retail, transportation, robotics, medical, and other technology-driven markets.
Since its initial ratification in 2005 COM Express has become one of the most popular embedded hardware standards in the world, spawning eight different Types, four different sizes, and three major revisions while retaining a modular architecture that promotes vendor interoperability and technology reuse.
The primary feature that sets COM Express apart from traditional single-board computers (SBCs) is the ability to plug off-the-shelf modules into custom carrier boards designed to application-specific requirements. In other words, a custom COM Express carrier board can be designed into a system to transport all necessary signals to and from subsystems and peripherals, and off-the-shelf COM Express processor modules can plug directly into the carrier and serve as the main controller. This dual-board architecture precludes the high-speed interfacing and signal integrity expertise users would otherwise require in the design of their own processor modules, reduces time to market, and provides a scalable upgrade path to newer modules should the application require more performance in the future.
COM Express modules connect to carriers and other hardware via connectors different standardized pinouts, the most common of which today are Types 6, 7, and 10. The latest revision to the COM Express specification, COM.0 R3.1, helps modernize these interfaces by adding USB4 to Type 6 designs, CEI sideband 10 GbE signaling for Type 7 modules, and PCI Express Gen 4 support across all module types. These join an array of other signals supported by the connectors, which can be seen in the diagram below.
The PICMG COM Express subcommittee maintains active working groups that will focus on evolving the technology with support for new interfaces for mid-range edge computing applications and more ruggedized mechanical variants for deployment in harsh environments.
Key Benefits & Features
- High performance with high speed serial interfaces, including PCI Express Gen 4, 10GbE, USB 3.0, SATA, LVDS, CAN, HDMI, and other high res graphics.
- Can be used standalone or in conjunction with a user-supplied carrier board that provides application specific I/O.
- When used with a carrier board, performance upgrades can be as simple as plugging in the latest commercially available module with the newest chip sets.
- 7 different versions are defined that balance cost, features, and performance while maintaining common connectors and mounting holes and common signaling where appropriate.
- General purpose embedded computing, including industrial control, transportation, data acquisition, medical, point of sale, man machine interface, digital signage, multimedia and communications.
- Ruggedized and high temperature range products are available for demanding applications, including mil/aero, rail, vehicular, and remote data acquisition.
- High speed and connectivity applications using up to 32 PCIe Express lanes and up to quad 10GbE interfaces. Includes high bandwidth applications such as data centers and video surveillance.