The Rise Of The Power Architect

By Ann Steffora Mutschler

Call them power czars, power gurus or power architects, this role within design teams is gaining importance with the need to understand, manage and control the power budget throughout the entire design process. As such, power architects are in high demand today with power architecture teams doubling in size within a year or two.

Driving the need for this highly skilled position is power estimation at the architectural level, usually done with Microsoft Excel spreadsheets, observed Ridha Hamza, sales and marketing director at Docea Power. “Those Excel spreadsheets have been developed by platform architects, the chipset guys. They took the initiative—and this is something we have seen in many companies—of assembling the spreadsheet, then they get caught and have to maintain it. Usually they are platform architects, very much in link with the marketing teams. Their first objective is to answer the marketing guys what is possible, what would be the impact of this change or decision and so on.”

However, what started as a better way to communicate with the marketing team can become an albatross. “Once [the platform architects] give numbers to customers, they have to comply with those numbers so they are liable for those numbers now. They go to the SoC implementation guys, the SoC and other ICs that they integrate in the chipsets and they have to make sure that these numbers are correct and they don’t diverge during the implementation phase,” he explained.

These tasks become exponentially complex because there is a lot of data to manage with versions and the architects must build a database that contains not only information on the ICs or the IPs but also on the use cases, Hamza said. “So they are in the middle of the IP teams, the system architects—which develop code for the system and software behind them—and as well as the packaging guys or the thermal experts which have to model the package.”

Not Just for Mobile Devices

Power architects used to mainly exist in the mobile and hand-held companies, because these were the companies that were really concerned about power, noted Kiran Vittal, senior director of product marketing at Atrenta. For this reason, there are dedicated people looking at power in terms of how to reduce power and how to architect the chip in such a way that it will have multiple power-down modes and other power features to optimize for power. “If you talk to the Apples and the Qualcomms, the ST-Ericssons of the world, they all have power architects,” he said.

Pete Hardee, low-power design solution marketing director at Cadence agreed. “Most of the major companies have specialists on low-power architecture. They have probably more specialists on the verification side of that, but definitely there’s usually one or a small group of people who own the overall power budget. That budget needs to be sliced and diced and policed so that everyone keeps to it. That power budget isn’t just one set of figures. It’s a set of figures for every major mode that the system is in. The tool that most people are using for that today is Microsoft Excel, and there are pretty involved spreadsheets that I’ve seen with various customers tracking all the components. It’s not necessarily component-level, but it does involve all the major design blocks and the status of those in a multitude of power modes and really keeping tabs of all of that. The power budget isn’t one number any more. It’s exceedingly complex.”

However, it’s not just the mobile folks concerned about power obviously, Vittal said.  Graphics, network and server chip companies are all extremely focused on power issues. In the case of networking chips, they may be concerned about power for different reasons such as to reduce cooling costs. In the case of server chips—from companies including Calxeda, which has ARM-based server chips that are consuming 10x lower power. “Everybody is concerned about power and even though they may not be hiring architects, they have dedicated people looking at power in the design teams.”

With all of the complexity in these low-power yet high-performance systems, are there enough engineers with right skills to go around?

Vittal says no. “Traditionally a lot of the stuff was being done at the gate level. Whenever you had power concerns, you would look at low-power libraries and look at different kinds of cells in your libraries to optimize for power. For example, you may have multi Vt cells and so on, so synthesis or place & route would automatically pick some low-power cells and implement the design. You can only get so much in the gate level. You cannot do much. But now, people are looking at a much higher level. What they are concerned about is, depending on how the chip operates—for example, if it’s a mobile chip it has a audio mode, it has a video mode, it has a normal phone mode—depending on the mode of operation they want to shut off everything else. This needs a lot of power planning. This is where all this power islands and power domains and voltage domains come in the picture and it needs a special expert.”

Barry Pangrle, solutions architect for low-power at Mentor Graphics said it’s just a matter of companies putting a priority on it and the fact that they’re doing it now is leading to position. “Even if you just go and look at different companies that are looking to recruit people quite often now they list specifically that they’re looking for people to work in power efficiency or able to reduce power of the designs they are working on. We’re starting to see this across a broader range too, not only in the RTL implementation part.”

He’s not alone in that assessment. “Ultimately I think what’s going to happen is that skill set is going to be absorbed into the chip and system architecture, said Cary Chin, director of marketing for low-power solutions at Synopsys. “Power is going to move up to the system level,  because the implications are so big with regard to the chip, the system, the software—the entire infrastructure. Right now the nomenclature might be ‘power architect,’ but I think that is really being absorbed as a function.”

This comment perfectly illustrates just how pervasive power awareness has become in design today and just how integral and indispensable the power architect is in the engineering infrastructure.