
In the mobile world we live in, many view products based on the X86 microprocessor architecture as technology from a bygone era.
However, X86 solutions abound in many everyday applications from our desktop and laptop computers to the servers and network solutions found in modern data centers.
Another area where X86 solutions abound is embedded computing applications. More than 20 years ago, the computing industry established a common vision of adapting desktop computer technology for embedded applications.
The original specification developed was PC/104™ enabling support for legacy PC interfaces while providing flexibility for future bus architectures.
The PC/104 family of embedded computing standards has continued to evolve. The PCI/104-Express™ system is one of many standards released to support the growth of PCIe in embedded computing applications.
PCI/104-Express™ Embedded PC Modules

The PCI/104-Express™ specification establishes a standard to use a high speed PCI Express® bus in embedded applications. It was developed by the PC/104™ Embedded Consortium and adopted by member vote in March 2008. The PC/104™ Consortium chose PCI Express® because of its full PC market adoption, performance, scalability, and growing silicon availability worldwide. It provides a new high-performance physical interface while retaining software compatibility with existing PCI infrastructure.
Incorporating the PCI Express® bus within the industry proven PC/104™ architecture brings many advantages for embedded applications including fast data transfer, low cost due to the unique self-stacking bus of PC/104™, high reliability due to the inherent ruggedness of PC/104™, and low term sustainability.

The PCI/104-Express™ standard specifies Samtec’s Q2™ QMS/QFS Series in a three bank (156 pin) orientation for module stacking. Samtec specifically designed mating connector sets, based on the QMS/QFS Series, with a 15.24 mm stack height for top and bottom board stacking. Q2™ has triple the wipe of many high speed mezzanine interconnects making it appropriate for rugged applications. The mating Q2 connector sets designed for PCI/104 Express applications are:
- ASP-129637-03 – 3 bank assembly, top (15.24mm)
- ASP-129646-03 – 3 bank assembly, bottom (15.24mm)
- ASP-142781-03 – 3 bank assembly, top (22.00mm)
PCI/104-Express™ OneBank

To offer system designers greater control over PCB real estate, the PC/104™ Consortium has developed PCI/104-Express™ OneBank. This new standard is an extension to PCI/104-Express™, and uses specialized single bank (52 pin) Q2™ connectors which mate to the traditional 3-bank connectors. Now, engineers can win back valuable board-edge real estate by only bringing the vital main-bus to cards with OneBank connectors. They are available in both 15.24 mm and 22 mm stack heights.
- ASP-129637-13 – 1 bank assembly, top (15.24mm)
- ASP-129646-22 – 1 bank assembly, bottom (15.24mm)
- ASP-142781-07 – 1 bank assembly, top (22mm)
New PCI/104-Express™ Standoff

Recently, Samtec has released a new standoff for PCI/104-Express™ systems. The JSOM series Micro Jack Screw Precision Board Stacking Standoff reduces the risk for component damage on boards for the Board Stack Height of 15.24 mm. A 22mm stack height option is under developemnent.
Please send inquiries of pricing, support and technical detail on JSOM Series here. Our standard experts can be reached at standards@samtec.com.
For more information on Samtec’s JSOM Series and related PC/104 interconnect, please download the following resources: