Important points to know about VPX and Open VPX (VITA 46.0/48.0/65.0)

Important points to know about VPX and Open VPX (VITA 46.0/48.0/65.0)

VPX (VITA 46) standards and OpenVPX are related but distinct sets of specifications that define standards for high-performance, ruggedized electronic systems used in various applications, particularly in defense and aerospace. Here is an overview of some common VPX standards and compare them to OpenVPX. 

VPX (VITA 46):

VPX is the foundational standard that defines the physical and electrical characteristics of VPX modules, backplanes, and connectors.

Form Factors:

VPX modules come in 3U and 6U form factors, with various configurations.


VPX backplanes are defined in the VITA 46 standard, supporting different data rates and configurations.


VPX connectors (P1, P2, P3) are specified in VITA 46, defining pin assignments and signal characteristics.


VPX enclosures must address cooling for high-performance applications.


VPX enclosures can be designed for rugged environments, but specific ruggedization standards are not part of VITA 46.


OpenVPX builds upon the VPX standard and extends it by defining additional profiles and design guidelines, promoting interoperability and modularity.


OpenVPX defines profiles that standardize system architectures and configurations, such as payload, switch, and slot profiles.


OpenVPX encourages the use of standardized modules and backplanes to create interchangeable components, facilitating system upgrades and integration.

Software Integration:

While primarily a hardware standard, OpenVPX also considers software aspects by defining profiles that specify the types of software and middleware that should be supported.



  • VPX (VITA 46) primarily focuses on the physical and electrical characteristics of components like modules, backplanes, and connectors.
  • OpenVPX extends VPX by adding system-level architecture and modularity considerations.


  • VPX (VITA 46) provides the basic building blocks but does not enforce interoperability beyond the hardware level.
  • OpenVPX defines profiles and guidelines for system-level interoperability, promoting more standardized system architectures.


  • VPX (VITA 46) allows for modular components but does not enforce or standardize modularity to the extent that OpenVPX does.
  • OpenVPX emphasizes modularity, making it easier to upgrade, customize, and integrate components within a VPX-based system.

Software Integration:

  • VPX (VITA 46) primarily addresses hardware standards.
  • OpenVPX includes considerations for software, specifying profiles for software and middleware, which can enhance system compatibility.


  • VPX (VITA 46) serves as the foundation for OpenVPX, so OpenVPX is often used in conjunction with VPX standards.
  • OpenVPX has gained more prominence in recent years due to its focus on system-level modularity and interoperability.

In summary, VPX (VITA 46) provides the core hardware standards for ruggedized electronic systems, while OpenVPX extends these standards to promote system-level modularity and interoperability. When designing or selecting components for a VPX-based system, considering both VPX and OpenVPX standards can help ensure compatibility and flexibility in your system architecture.

Different version of VPX 46 and 48

VITA 46, commonly known as VPX (VMEbus International Trade Association 46), has several versions and standards that have been developed over the years to meet the evolving needs of the embedded computing industry. Each version introduces improvements and enhancements to the original VPX standard. Here are some of the notable versions of VPX:

VITA 46.0:

This is the original VPX standard, which established the basic mechanical and electrical specifications for VPX systems. It defines the 3U and 6U form factors, backplane dimensions, power supply configurations, and connector assignments for P1, P2, and P3.

VITA 46.1:

This standard introduced enhancements to VITA 46.0, including additional backplane profiles to support higher data rates (e.g., 6.25 Gbps) and improved signal integrity. It also addressed the handling of power and ground pins for better power distribution.

VITA 46.3:

VITA 46.3 extended the VPX standard to include support for Rear Transition Modules (RTMs). RTMs provide additional I/O interfaces and functionality to VPX modules, enhancing system flexibility.

VITA 46.4:

VITA 46.4 introduced the concept of “conduction-cooled” VPX modules and systems, which are designed to operate in extreme environmental conditions, including high temperatures and rugged environments. Conduction-cooled modules use special heat sink designs and thermal interfaces to dissipate heat effectively.

VITA 46.6:

VITA 46.6 added support for Air Flow-By (AFB) cooling, which is a cooling technique that utilizes air flowing perpendicular to the VPX cards’ front panel to improve thermal management.

VITA 46.9:

VITA 46.9 introduced the concept of “VPX REDI” (Ruggedized Enhanced Design Implementation), which aims to enhance the ruggedness and reliability of VPX systems for military and aerospace applications. It includes specific requirements for ruggedized components and connectors.

VITA 46.10:

VITA 46.10 defined additional profiles and guidelines for OpenVPX, an extension of the VPX standard that promotes interoperability and modularity in VPX-based systems. OpenVPX includes profiles for different system architectures, such as payload, switch, and slot profiles.

VITA 46.11:

VITA 46.11 focused on enhancements to the OpenVPX standard, refining profiles and introducing new features to improve interoperability and system integration.

VITA 48 is a family of standards that define mechanical specifications for the design and construction of conduction-cooled Eurocard-based modules used in VPX (VITA 46) and other embedded computing systems. VITA 48 standards specify the physical dimensions, thermal design, and cooling techniques for these modules. Here are some notable versions and extensions of the VITA 48 standard:

VITA 48.0:

The original VITA 48.0 standard, titled “VPX Conduction Cooling,” provides guidelines and specifications for conduction-cooled modules and associated connectors used in VPX systems. It defines the module’s mechanical characteristics and thermal considerations for effective heat dissipation through the module’s edges.

VITA 48.1:

VITA 48.1, titled “VPX Conduction Cooling: Frame Construction,” extends the VITA 48.0 standard by specifying additional mechanical details related to the frame construction of conduction-cooled modules. It provides guidelines for constructing the frame, which is an essential part of the conduction-cooled module’s thermal management.

VITA 48.2:

VITA 48.2, titled “VPX REDI (Ruggedized Enhanced Design Implementation) Conduction Cooled,” further enhances the VITA 48 standard to address ruggedization and increased environmental resilience for conduction-cooled modules. This extension adds specific requirements and guidelines for conduction-cooled modules used in rugged or harsh environments.

VITA 48.3:

VITA 48.3, titled “VPX: Mechanics for Fixed Modules,” defines mechanical specifications for fixed modules in VPX systems. Unlike traditional VPX modules, which are typically removable, fixed modules are permanently installed in the chassis. This standard outlines the mechanical requirements for such modules.

VITA 48.4:

VITA 48.4 is an extension that specifies the mechanics for VPX REDI (Ruggedized Enhanced Design Implementation) hybrid modules. These modules combine both air-cooled and conduction-cooled components, making them suitable for applications that require a combination of cooling methods.

VITA 48.5:

VITA 48.5 is an extension that focuses on further enhancing the ruggedization of VPX REDI modules. It includes specifications for specialized connectors and gaskets to improve environmental sealing and robustness.

VITA 48.7:

VITA 48.7, titled “VPX REDI System Design Using Modified COTS Modules,” provides guidelines for designing VPX REDI systems using modified Commercial Off-The-Shelf (COTS) modules. It addresses considerations for adapting existing modules to meet ruggedization requirements.

It’s worth noting that these versions and standards are not necessarily exclusive, and many VPX systems may incorporate features from multiple versions to meet specific requirements. The choice of which version or combination of standards to use depends on the specific application and the level of ruggedization, performance, and interoperability needed for the system. Engineers and system designers should refer to the latest VITA documentation and industry-specific requirements when selecting the appropriate VPX standard for their projects.

Different versions of VITA 65 standard

VITA 65 standard, also known as “OpenVPX,” is a framework that defines a modular and open standard for VPX (VITA 46) systems used in rugged and embedded computing applications. While VITA 65 itself has remained relatively stable as a framework, it has seen the development of various profiles and extensions over time to address specific needs within the VPX ecosystem. Here are some notable versions and developments related to VITA 65:

VITA 65.0:

This is the foundational VITA 65 standard, which defines the overall framework for OpenVPX. It sets the structure for creating profiles and modules within the OpenVPX framework.

OpenVPX Profiles:

Within VITA 65, there are various profiles that have been developed to address specific system architectures, roles, and performance requirements. These profiles include Payload, Switch, Slot, and Development Chassis profiles, among others. Each profile defines a set of module slots, power and cooling schemes, and I/O configurations suitable for different applications.

VITA 65.1:

This extension of VITA 65 introduced additional profiles and enhancements to existing profiles. It refined some of the definitions and requirements for OpenVPX modules and chassis.

VITA 65.2:

VITA 65.2 focused on enhancing the OpenVPX standard for high-speed data rates. It introduced profiles optimized for higher data transfer rates, such as the High-Speed Backplane (HSBP) profile, which accommodates data rates of 25 Gbps and beyond.

VITA 65.3:

VITA 65.3 continued the development of OpenVPX by introducing profiles for security and safety-critical applications. This extension addressed the specific needs of systems where security and safety are paramount.

VITA 65.4:

This version extended OpenVPX to support optical interconnects. It introduced profiles for optical backplanes and modules, accommodating optical data links for high-speed and long-distance communication within VPX systems.

VITA 65.5:

VITA 65.5 is an ongoing effort aimed at further refining and expanding the OpenVPX standard to keep pace with evolving technology and application requirements. It may include updates and additional profiles as needed.

To access the most current information and developments regarding VITA and OpenVPX, visit:

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