Relieved connector makers say the newest spec of the PCI Industrial Computer Manufacturers Group (PICMG) for next-generation telecom equipment will spur component growth in 2003, despite a prolonged downturn in the communications industry.
Those same connector makers are also crossing their fingers that the spec will drive growth for standard off-the-shelf solutions beyond the telecom market, since other industry sectors, such as datacom and military equipment manufacturers, are showing interest in the spec, called AdvancedTCA (Telecom Computing Architecture).
That interest is most welcome, since the market for telecommunications-grade equipment has dwindled to roughly $50 billion from $100 billion at its peak, analysts estimate. Telecom companies such as Lucent Technologies and Alcatel are trying to find where they fit in this new market environment, and are working to improve overall efficiency. Part of that process means limiting the number of platforms they ship, to reduce training, spare parts and software, said Joe Pavlat, PICMG president (Wakefield, Mass.).
Lucent, for instance, no longer wants, nor has the ability, to build equipment in-house; instead, it wants an open public standard with multiple vendors producing product, Pavlat said. Moreover, with layoffs still dominating the industry, companies simply lack the engineering resources to support the 300 different platforms they deploy, he said.
The core AdvancedTCA specification, PICMG 3.0, defines mechanical and electrical requirements as well as board sizes, integrated systems management structure and regulatory guidelines for next-generation telecom equipment. Subsidiary specifications for link technologies like 3.1 for Ethernet, 3.2 for Infiniband, 3.3 for Star Fabric and 3.4 for PCI Express will be published throughout 2003.
The spec provides OEMs with a backplane design that suits their architectures and that will initially support Gigabit Ethernet, StarFabric and Infiniband, with later support for Xaui and RapidIO, said Tim Minnick, senior systems interconnect engineer for Tyco Electronics (Harrisburg, Pa.).
AdvancedTCA was designed initially to offer carrier-grade equipment makers a standard backplane design that addressed serial architectures, which have become prevalent in telecom and enterprise networking during the past five years. However, the spec also had to provide manufacturers with standard, modular off-the-shelf solutions and be viable for up to 10 years.
Michael Munroe, director of marketing at Erni Components Inc. (Chester, Va.), said the PICMG 3.0 committee has developed and defined the connector implementation, trace routing and more aspects of the backplane environment than in almost any previous standard.
In addition to providing a standard backplane design, the spec had to accommodate production by multiple vendors. PICMG 3.0 identifies two key connectors for Zone 1 (power) and Zone 2 (data transport), while a Zone 3 connector for the rear transition module has been left open for greater system flexibility.
Munroe said the committee had a hard time choosing the data transport connector. The minimum requirements called for a connector that could be used in differential signaling applications and provide individual links of 3.125 Gbits/second, Munroe said.
Besides providing support for high-speed differential signaling, the committee wrestled with key issues such as mechanical constraints, cost, availability and manufacturability in choosing a connector. On the technical side, implementation on the board, trace routing support and level of crosstalk helped determine the connector of choice.
Pavlat said that in addition to multisource availability, the two most important features the committee looked at were speed and density. The majority of fabrics such as Infiniband, Gigabit Ethernet and PCI Express all work at 3 Gbits/s so any connector chosen by the committee had to be capable of handling very high frequencies and very high densities, he said. "A PICMG 3.0 system in its full mesh topology is capable of an aggregate bandwidth of 2.5 terabits/s and that's a tremendous amount of traffic."
PICMG for AdvancedTCA selected the Erni-Tyco ZD high-speed backplane connector as the high-speed data transport connector. Known as the Erni ErmetZD and Tyco Z-Pack HM-Zd connectors, they meet or exceed performance and shielding requirements for next-generation equipment by using low-voltage differential signaling and low crosstalk, low skew, improved trace routing and rugged housing-all key elements for next-generation, high-speed designs.
To ensure an adequate supply is available, several other connector manufacturers have either applied for or are looking at licensing the design to build the ZD connectors for PICMG applications.
Both Erni and Tyco also have plans to extend the ZD family of connectors. Designed for applications with data rates of between 3 Gbits/s and 5 Gbits/s, Erni, for instance, recently expanded the Ermet ZD differential connector family to include 2-pair modules with 20 differential pairs.
Both the vertical male connector modules for backplanes and the angled female modules for the plug-in cards are constructed of 10 contact wafers (40 signal contacts and 20 ground contacts). The system is also available in three- and four-pair styles.
"In anticipation of the types of applications that our customers might need interconnections for, we are expanding the product line, not always for PICMG, but for the general market as well, said Bob Hnatuck, product manager for Tyco Electronics. "But if this follows a similar course as the [PICMG] 2.x series, we have a pretty good idea of the types of interconnects that will be needed."
Tyco has already released cable assemblies for the HM-Zd line and is in the process of releasing its line of HM-Zd right-angle headers.
On the power side, PICMG chose the Positronic Industries Inc. power connector that was specifically designed for the AdvancedTCA application. While this connector is often considered a custom device, the design is not proprietary. Positronic has written a detailed spec for the power connector that is included in the PICMG 3.0 core specification.
The major reasons for the new design was that PICMG 3.0 needed a connector in a single small package that would bring power off the backplane to the card, interface with high-voltage test circuits and provide hardware management and geographic addressing, according to Gino Nanninga, vice president of sales at Positronic (Springfield, Mo.).
In addition, the connector needed to meet high reliability requirements as well as handle high currents and meet 48-volt dual redundant power requirements. Other features on PICMG's wish list for the power connector included 2-mm blind mating and four levels of sequential mating on the contacts. Such requirements pushed the envelope on what was currently available in the industry for power connectors, Nanninga said.
"AdvancedTCA boards are capable of dissipating 200 watts each, so when you have 16 boards in a rack, that's 3,200 watts, which is about three or four times higher than any other open standard has attempted to deal with," Pavlat said.
Positronic developed an IEC-style product spec that is incorporated in PICMG 3.0 for the power connector.
The connector maker is ready to support 3.0 with volume production. The company is also in the process of developing new variants that include smaller packages with fewer contacts, and connectors with fewer signal contacts but with more power contacts.
For Zone 3 connection to the rear transition module, just about any high-density, high-speed or coaxial connector can be used. In addition, the connector can be either optical or copper as long as it fits into the space provided.
Molex Inc., for example, is interested in this application. The company currently offers several connectors that fit the application, including its OmniGrid 2.5 DIN connectors and six-row or eight-row VHDM connectors. Molex also offers optical connectors including MT, SC and LC versions that would fit with a bulkhead mount.
Erni Components Inc.
Positronic Industries Inc.