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Dynamic Voltage Scaling with the XScale Embedded Microprocessor

  • Lawrence T. Clark
  • Franco Ricci
  • William E. Brown
Part of the Series on Integrated Circuits and Systems book series (ICIR)

The XScale Microprocessor

The XScale microprocessors [1] were intended as a follow-on to the StrongARM microprocessors [2] developed at Digital Equipment Corp. The XScale work began in 1998 to design a microprocessor that would be embedded in high-performance “tethered,” i.e., line-powered, as well as handheld (battery-powered) system-on-chip (SOC) ICs. The ability of the processor core to operate over a wide range of supply voltages (VDD) is key to achieving both high-performance and low power consumption across such a wide application range. Using the same microprocessor core in many, diversely targeted ICs, maximizes the core development return on investment.

Dynamically scaling the power supply to different voltages (VDD) to fit the application that is presently running maximizes both overall performance vs. power and energy efficiency. It was thus deemed critical to the XScale effort. Such a capability had been suggested by [3] and had been a topic of university research [4]...

Keywords

Clock Generation Voltage Control Oscillator SRAM Cell Dynamic Voltage Scaling Core Clock 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Lawrence T. Clark
    • 1
  • Franco Ricci
    • 2
  • William E. Brown
    • 3
  1. 1.Arizona State University
  2. 2.Marvell Semiconductor Inc.Marvell
  3. 3.Ellutions, LLCEllutions

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