In the need for speed, design engineers may have to choose between upgrading or completely redesigning - interconnect products should support both, write Sandy Barr and Adrian Hyner
Design engineers are perpetually faced with the challenge of squeezing higher speeds and better performance from their electronic systems. From consumer electronics to industrial applications, the movement toward more sophisticated software, multi-use devices, serialisations, flash memory, interactive video and higher bandwidth are driving the need for speed.
High-speed backplane systems
Nowhere is this trend more true than in the realm of high-speed backplane systems. For example, storage systems, computing systems and routers have become faster than that which a typical high-speed backplane system can handle today. All of these systems are processing and passing along more data at more rapid rates, and faster backplane interconnects and systems are needed to keep pace with the demands.
Backplane applications using 2mm hard metric connector technology (per IEC 61076-4-101 standard), such as VME bus (VME 64x) and CompactPCI backplane applications in areas such as military, medical electronics, enterprise computing, telecommunications, and industrial and factory automation, require more speed than ever. This particular platform is highly complex in technology and segments served, and the applications it supports are diverse. In fact, more than 60 companies provide input to the PICMG standard.
When faced with the demand for higher speed and better performance, design engineers face two choices: redesign a completely new system(s) with a completely new interconnect, backplane, daughter card electronics, and other hardware and software systems to increase throughput three to four times over its current state; or upgrade the existing deployed system, which can squeeze more speed, power and time, sometimes three to five more years of life, out of it.
Both approaches have their advantages and disadvantages, and it's not always a matter of one versus the other. Depending upon the circumstances, some organisations may decide to combine the two.
Telecommunications
A good example of this is found in the telecommunications industry. Many telephone companies are reconditioning and upgrading their traditional copper networks even as they deploy new fibre optic networks, and usually they're integrating the two. (Europe in particular is driving hard towards Next Generation Networks, which demand high-speed performance for voice and Internet protocol services, creating many opportunities for system upgrades.)
In terms of interconnect products, a handful of vendors have taken the approach that designing new systems is the way to go. A number of suppliers produce interconnect solutions to support the next generation of VME and Compact PCI systems and can transfer data at up to 10Gbit/s.
However, it requires a complete new redesign of the backplane, daughter card, hardware and software. Such changes are expensive and disruptive. Often, mission-critical systems simply cannot be taken offline to increase speeds. This is especially true in the defence industry.
Redesign drawbacks are primarily cost and time. It typically takes two to three years to complete a redesign and get it qualified. That's two to three years of investment with no return. Also, designers run the risk that their new system may not get qualified.
On the other hand, upgrading a current system can make much more sense financially. This is particularly true for incumbent vendors. It's far cheaper and less time-consuming than redesigning. It removes the risks of acceptance and qualification. And it allows quick and seamless movement to a new level of performance, with the intent that their products are delivered to the marketplace first. Plus, upgrading can buy time for design engineers to develop new technology and leapfrog their competitors.
Upgrading existing 2mm hard metric connector based systems
Until recently, however, there were no interconnect products available on the market to support upgrading existing 2mm hard metric connector based systems in a convenient, cost-effective manner.
Multi-gigabit per second interconnection solutions compatible with existing VME infrastructure were once considered impossible without an expensive, disruptive upgrade or system redesign. And some mission critical systems simply cannot be taken offline in order to increase speeds.
However, this situation has recently changed, for instance with the introduction of new connectors from 3M that enable a leap in speed to 5Gbit/s while being able to plug into existing 2mm hard metric connectors.
Companies in various market segments have already accepted the upgrade approach for a variety of reasons. For example, a military electronics company chose the upgrade approach over redesign to support higher backplane speeds and higher speed I/O for military systems that could not be taken out of service.
An enterprise switch vendor chose the upgrade approach to glean additional years from their already deployed switch backplanes by installing upgraded higher speed daughter cards. This approach resulted in a high return on investment and bought time for developing their next generation system.
The obvious disadvantage to retrofitting is that the upgraded system will never be as powerful as a completely new system. The upgrade, using new interconnect technology, might support five RapidIO lines; whereas a new system might offer ten.
Performance and cost trade-off
The question is whether the increased performance worth the cost trade-off. In situations where systems cannot be taken offline and financial return on investment is a priority and next generation speed and performance isn't needed quite yet, upgrading makes sense.
No two situations are going to be alike and there are a number of factors to consider when choosing backplane connectors to support greater demand for speed.
The good news is that the interconnect industry has risen to the challenge and now offers designers of high-speed backplane systems a full range of options to support either complete replacement or upgrade.
Sandy Barr is a product development specialist in 3M Electronic Solutions division and Adrian Hyner is sales and marketing manager, electronics at 3M UK.