COM Express

COM Express is a PICMG specification for x86 -based Computer-on- Module ( COM). COM Express Computer-on- modules integrate the core functionality of a bootable PCs such as CPU, GPU, memory, and standard interfaces to a module that is installed over a maximum of two connectors on an application-specific carrier board. COM Express is based on the 2003 presented by Intel and Kontron ETXexpress form factor, but was renamed by the PICMG COM Express in the course of the specification.

COM Express specifies both the dimensions of the module, placement of the mounting holes as well as the placement and pin assignment (pin -out type) connectors to the carrier board. These lead the typical PC serial interfaces such as PCI Express, USB, audio, graphics and Ethernet out to the carrier board. By establishing the pin assignment in the so-called pin-out types is to ensure that COM Express modules remain interchangeable, so that COM Express afterwards can still be upgraded with the new COM Express Computer-on- Modules also.

Pin-out types

Currently, the COM Express specification PICMG defined seven different pin-outs. The most common pin-out type 2 is the latest pin -outs, type 6 and type 10, 2.0 of the COM Express specification were added in early 2010 with the revision to incorporate up to three digital display interfaces parallel to the PCI Express Graphics Port.

Module sizes

The specifications define four module sizes:

  • Extended 155 mm x 110 mm
  • Basic 125 mm x 95 mm
  • Compact 95 mm x 95 mm
  • Mini 55 mm x 84 mm (Type 1/10 pinout )

COM Express specification

The COM Express specifications ( COM.0 ) is defined by PICMG. It can be purchased for a fee of PICMG.

  • Rev. 1.0 2005
  • Rev. 2.0 2010
  • Rev. 2.1 2012

COM Express Carrier Design Guide

The COM Express Carrier Design Guide PICMG provides additional information for the development of application-specific carrier board for COM Express COMs. In addition to reference plans for external circuitry to implement the various peripheral functions of COM Express modules, it also describes the supported bus systems and continue as other peripherals and expansion slots Express -based system should be integrated into a COM. The COM Express Carrier Design Guide is available both on the PICMG website, as well as in the various embedded manufacturers.


  • Aaeon
  • Adlink
  • Advantech
  • Congatec
  • GE Intelligent Platforms
  • Kontron
  • Lippert Embedded
  • MSC Vertriebs GmbH
  • VIA Technologies GmbH