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Defense Speak Interpreted: What’s a VITA?

Ever wonder how military electronics users could swap out circuit cards rapidly and keep their defense systems running? What about a “hot swap” of a circuit card that was questionable? How would defense depots keep enough unique circuit cards on hand to maintain the various systems in times of heavy use? The Department of Defense started to worry about those issues over 30 years ago and has helped private industry develop a highly sophisticated set of standards for circuit card input/output (I/O) to make quick change possible. 

This evolved into the “VITA” standards, used widely today both in and outside defense. VITA association origins formally track back to 1984 and have evolved to a nonprofit association with over 100 working groups on various aspects of key computer bus, board, and system standards.  

VITA stands for VMEbus Industry Technology Association–but what is a VMEbus? That, itself, traces back to work on microprocessors at Motorola (does anyone remember when Intel was not the world CPU leader?). Motorola computer module developers standardized on “Versa Module Europa” or “Versa Module Eurocard” (VME), which is now standardized in ANSI/IEEE 1014-1987. According to Wikipedia:

“Eurocard is a European standard format for printed circuit board (PCB) cards that can be plugged together into a standard chassis which, in turn, can be mounted in a 19-inch rack. The chassis consists of a series of slotted card guides on the top and bottom, into which the cards are slid so they stand on end, like books on a shelf. At the spine of each card is one or more connectors which plug into mating connectors on a backplane that closes the rear of the chassis.”^[1]  

One concept that VITA carries forward is the “height mounted vertically” of an assembled module–defined in increments of “U”–which turns out to be 1.75 inches. VITA modules are frequently referred to as 3U or 6U. 

You see that the standard module concept has morphed much further than ever thought possible, but why? The key to the ever-expanding VITA concept is “open architecture” and “modular computing systems.” From the VITA website:

“VITA is an incorporated, non-profit organization of vendors and users having a common market interest in real-time, modular embedded computing systems. VITA is accredited as an American National Standards Institute (ANSI) developer. VITA provides members with the ability to develop and to promote open technology standards.” ^[2] 

One of the keys to this cooperation is the VITA-driven patent policy that participants must disclose their patents pertaining to the development of a standard, and also the most restrictive patent licensing that would be available. This process received U.S. Justice Department anti-trust approval some 14 years ago. I believe this aspect has since been covered in this IPC Anti-Trust statement:

“IPC standards shall be developed in accordance with applicable antitrust and competition laws, and meetings amongst competitors to develop IPC standards are to be conducted in accordance with these laws.”

But what really drove the need for modularity? The need to use CPUs in computers did not require modules—most of those use motherboards for desktop or personal computers. This occurred around 1980. (I can still remember the first time I heard about a “laptop” at an IPC Technology Marketing Research Council meeting at that time. I thought, “Why would someone ever use a computer on their lap when there is a perfectly good table nearby?”) These individual computers used small, low-cost microprocessors that resulted in a greatly reduced size and price. Industrial control systems, using these microprocessors, worked great in those applications, but they had two major drawbacks: durability and ease of modification.

Thus, the VMEbus architecture was born in 1981. The VITA website further explains:

“The new design combined the VERSAbus electrical specification, which was based on microprocessor technology, with the rugged and modular Eurocard packaging system. Both were proven, off-the-shelf technologies. The resulting combination was successful because it solved the durability problem and could be easily adapted to a wide variety of applications. However, this was only part of the story, as there was also a business strategy behind VMEbus that solved some very difficult market problems.”^[3]

To better understand the extensive development of VITA activities, a look at their standards development follows from their technology map.  You can see VITA now extends from the original core technology all the way through systems specifications. 

Figure 1: A look at the VITA technology roadmap illustrates its standards development.^[4]

Bringing it back to defense–where are VMEbus and VITA standards used in the military, specifically battlefield command and control systems, ground and flight radar control systems, tank and gun controls, communications, avionics and many others? You can see that these are somewhat like the outlined industrial applications. In fact, “while the “V” in “VME” actually stands for “Versa” (as in “Versa Module Eurocard”), it could arguably also stand for “venerable”—especially in the defense and aerospace commercial off-the-shelf (COTS) market. For decades prior to the advent of the VPX architecture in 2006, VME was unquestionably a de facto board standard for rugged open architecture systems. Today, there are thousands of VME boards installed in the field and untold millions of dollars invested in hardware and systems software currently used on those deployed systems.^[5] 

Today, VITA activities are centered on four core membership activities:

FMC Community (FPGA Mezzanine Card from VITA 57, www.vita.com/fmc)

• IO mezzanine modules, which connect to carrier cards
• A high-speed connector family of connectors for IO mezzanine modules
• The electrical connectivity of the IO mezzanine module high-speed connector
• The mechanical properties of the IO mezzanine module 

VPX Community (www.vita.com/vpx)

• “The purpose of the VPX Community is to establish an ecosystem of interested parties that promotes and creates name recognition, as well as grow adoption of the VPX specifications and technology.
• The alliance is responsible for educating, training, and promoting the potential capabilities of the VPX family of specifications and informing the broader community and press.
• The U.S. Department of Defense and other users are mandating improved implementation of open standards and interoperability. VPX specifications have been focused at the board level, but there is also a need for considering system-level requirements to improve interoperability and reduce customization, testing, cost, and risk.
• The OpenVPX Systems Specification defines an architecture framework that manages and constrains module and backplane designs, including defining pin outs, and sets interoperability points within VPX while maintaining full compliance with VPX.” 

Reliability Community (www.vita.com/reliability)

• The purpose of the Reliability Community is to establish an ecosystem of interested parties that promotes and creates reliability practices.
• Electronics failure rate predictions are typically used for comparative assessments, reliability analysis, cost trade studies, availability analysis, spares planning, redundancies modeling, scheduled maintenance planning, product warranties and guarantees. Reliability predictions are not meant to represent the field reliability (i.e., mean-time-between-maintenance, mean-time-between-removals, etc.).
• VITA 51.0 and the subsidiary specification VITA 51.1 define consistency and repeatability for mean time between failure (MTBF) calculations. VITA 51.3 provides information on how qualification levels and environmental stress screening (ESS) influences reliability. VITA 51.2 defines standard methods for using physics of failure in reliability prediction.
  

VNX Community
The purpose of the VNX Community is to establish an ecosystem of interested parties that promotes and creates name recognition, as well as grow adoption of VNX technology. The community is responsible for educating, training, and promoting the capabilities of VNX and informing the broader community and media.

In summary, now ANSI/VITA standards go from 1.0 to 86.00, however, not all numbers have survived and there are vacancies. Standard names may include up to 2 decimal places and standards use the number and the most recent year of revision or review. One example is ANSI/VITA 46.11-2015, named VPX: System Management. VITA is a well organized industry standards organization promoting open architecture, and new ways of organizing electronics module interconnection. I can only imagine that the myriad constructions of substrate-like-circuits, 2.5 and 3D constructions, and fan-out panel level packaging could currently use a good dose of open architecture and a self-policing industry association like VITA. 

References   

1. https://en.wikipedia.org/wiki/Eurocard_(printed_circuit_board).
2. https://www.vita.com/   
3. https://www.vita.com/page-1855175
4. https://www.vita.com/TechnologyRoadmaps
5. https://www.curtisswrightds.com/news/articles/long-live-vme.html 

Dennis Fritz was a 20-year direct employee of MacDermid Inc. and is retired after 12 years as a senior engineer at SAIC supporting the Naval Surface Warfare Center in Crane, Indiana. He was elected to the IPC Hall of Fame in 2012.