A Resonant Global Clock Distribution for the Cell Broadband Engine Processor

Abstract

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> Resonant clock distributions have the potential to save power by recycling energy from cycle-to-cycle while at the same time improving performance by reducing the clock distribution latency and filtering out non-periodic noise. While these features have been successfully demonstrated in several small-scale experiments, there remained a number of concerns about whether these techniques would scale to a product application. By modifying the Cell Broadband Engine Processor to incorporate a large resonant global clock network, power savings with full functionality is demonstrated over a 20% range in clock frequencies, and a 6–8 Watt power savings at 4 GHz. This was achieved by changing one wiring level and adding an additional thick copper level to create inductors and capacitors. </para>