This ran originally in EE Times
by R. Colin Johnson
Excessive power consumption has become the chief roadblock to further scaling of semiconductors, threatening to stall advancement in all electronics sectors-everything from further miniaturizing mobile devices to revving supercomputers.
While the causes are rooted in the immutable laws of physics and chemistry, engineers have devised a novel set of innovations that are mitigating the problem today and that promise to reinvigorate the chip industry tomorrow.
Here are the top five ways to reduce power on future ICs. They are already in development, and collectively they hold the promise of solving the problem for good within the decade.
Electronic design automation tools can optimize for low power by enabling teams to co-design for it from the very beginning. In fact, the developers of lowest-power processors and systems-on-chip in the industry achieved their advantage not only by optimizing architectures and materials, but also by
co-designing packaging, power sources, RF circuitry and software to minimize power without diminishing performance or inflating cost.
"Building low power requires a holistic approach across technology, design methodology, chip architecture and software," said David Greenhill, director of design technology and EDA at Texas Instruments (Dallas).
TI has set the bar for low-power devices by optimizing each subsystem using pioneering techniques, such as building its own process technologies to balance off-mode leakage with active-current performance, or using voltage and frequency scaling to define a variety of power-saving operating modes.
"The first step is knowing the goal of the product from a performance and power perspective. Once those goals are determined, the process can be designed to provide the required performance without exceeding the device's power budget," said Randy Hollingsworth, 28-nanometer platform manager at TI.
EDA tools have been key to consistently achieving these lower-power goals, but sometimes they require a few iterations around the design loop, since estimates of power consumption with conventional EDA tools are only accurate near the end of the design cycle. For future ICs, power consumption estimates need to be accurate as early as possible in the design cycle.
Providers of a few specialized tools have picked up that baton. Atrenta Inc. (San Jose, Calif.), for instance, makes a tool called Spyglass Power that performs power consumption estimation, reduction and verification using the standard register-transfer level (RTL) descriptions that are available from every major EDA tool very early in the design cycle.
"Today, engineers want to estimate power very early in the design process," said Peter Suaris, Atrenta's senior director of engineering. "You can no longer wait until the end of the design cycle to estimate power consumption; you need to co-design for power at the RTL level, and make changes in your design to conserve power right from the beginning."
Atrenta reckons that its specialized power conservation tools can estimate the final power budget within 20 percent, while its power reduction tools can shave up to 50 percent off the energy consumed by the final design.