SAN JOSE, Calif. As signals move deeper into multi-gigabit territory, engineers are calling for more attention to the rising problems of modeling the interrelated affects of power, signaling and timing. Several sessions will deal with the issues at next week's DesignCon (Feb. 4-7) in Santa Clara, Calif.
"About 40 percent of our time in meetings for this conference was devoted to how we cover co-design to handle issues such as power noise. It will be a big focus area," said Terry Morris, conference chairman and a fellow in the high performance systems group at Hewlett-Packard.
Different tool sets address the issues separately at the levels of chip die, chip packages, boards and power supply design. That means systems that meet all their signal and timing margins may not work right when components from other vendors are swapped into the design.
"When you are sending multi-gigabit signals across products all the pieces have to work together," said Morris. "Quite a few tool vendors say they handle this co-design issue, but the reality is most engineers have to pick and choose point tools they like and staple them together," he added.
Large companies such as HP and IBM have created such custom tool flows. But merchant tool vendors have yet to step up to the plate with integrated power, signal and timing analysis products, he said. "Some see this as a power problem, and others see it as a signaling problem," he added.
Specifically, power integrity analysis is required to predict how switching noise will affect an interface's timing budget, according to a DesignCon paper to be presented by tool vendor Signal Integrity Software Inc. (SiSoft; Maynard, Mass.).
"Everyone is looking for what is the right model to integrate power analysis in with everything else," said Todd Westerhoff, a vice president at SiSoft and former lead signal integrity engineer at Cisco Systems.
Understanding the level of precision an analysis needs to reach to accurately predict its operating margins is critical, he added. "The easiest thing is to slip into a world of analysis overkill," said Westerhoff.