Powering the Growth in Data Communications Infrastructures

July 22, 2016 // By EDN Europe
By Martin Hägerdal, Architects of Modern Power Spokesman and Head of Ericsson Power Modules

Numerous reports trumpet the astronomic growth in Internet data traffic expected over just the next three or four years, based on forecasts for increased consumption of on-demand video and use of cloud based services coupled with the anticipated growth in data from devices connected to the Internet of Things (IoT). The latter phenomenon, according to Cisco, is set to see 50 billion things connected to the Internet by 2020, with network capacity needing to support more than a zettabyte (1021 bytes) of data daily as early as 2018 for what Cisco and others are now calling the “Internet of Everything” (IoE).  

Not surprisingly, handling this vast amount of data poses a serious challenge in growing the network and data center infrastructure to store and serve all this information. New generations of equipment that benefit from more advanced and more efficient processors along with ever larger and more powerful FPGAs are helping to meet this requirement. However, equally challenging is the need to power all these new devices with their multiple supply rails operating at ever-lower voltages, especially when load currents can rapidly change in response to dynamic system-level demands.

This challenge is more than simply deploying efficient and extremely reliable power conversion modules throughout the distributed power architecture that is typical employed by such systems. Rather, it demands units that are responsive to varying loads, which can quickly change from minimum to maximum, and are highly efficient at all load levels, including light loads. Consequently, network power system designers are increasingly turning to digital power solutions that allow software to control the operation of all the power supplies; from front-end ac-dc converters, through intermediate bus dc-dc converters (IBCs), to the final point-of-load (POL) converters that are situated on the processor and networking cards in the servers and communications equipment racks.

Herein lies a further challenge. While most manufacturers of digital power modules have adopted PMBus™ as a common protocol for software control, the implementation of PMBus commands is not consistent, i.e. the way in which a module responds to a given command cannot be guaranteed from one vendor to the next. This thwarts the ability for equipment makers to procure components like power supply modules from multiple sources, as they did previously by relying on industry standards like DOSA and POLA for mechanical footprint and electrical connectivity.

Stepping into this breach is the Architects of Modern Power® (AMP Group), founded some two years ago by three leaders in the power supply industry: CUI, Ericsson Power Modules and Murata. Their aim has been to streamline digital power design with standards that enable drop-in replacement compatibility between power modules and ensure the security of supply demanded by system OEMs, through commercial availability from more than one vendor.

Close collaboration between each of the companies’ engineering teams has allowed the AMP Group to develop software-defined power architectures that take full advantage of its members’ respective digital converter technologies while also designing in that extra element of compatibility that means its modules respond in the same way to PMBus commands. Hence its digital