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Tomorrow Computers eventually become ubiquitous,
eliminating the hassle of carrying
Yesterday Innovative technologies arose to
enrich peoples lives
Today Gadgets are not only functional but also
mobile, allowing enjoyment anytime and anywhere
Deployment of Low Power Modes For E-Textile
Applications
Technology
Motivation
Shorter Battery Less Mobility
High Power Consumption
High Speed
Can power be saved when high speed is not
required?
Yes, by going into low power modes !
Speed reduced or parts turned off for idle waiting
Full-speed processing for essential computation
Application
Texas Instrument MSP430 F1232
Low Power Modes (LPM)
Power-efficient design
Measurement Results
Implementation
Challenges

• Problems
• Interrupt wake-up requires running timer
• The period to sleep for has to be
  pre-determined at compile time

• Solutions
• Soldered an oscillator onto the chip as timer
  source
• Calculated how long software busy loops take and
  replicated in hardware

• When its time to go low-power
• Turn on timer to generate interrupts that will
  later wake up the CPU
• Set the timer period to be the length of sleep
  required
• Go into low power mode
• Measure the current once the application reaches
  steady state.

Substantial savings of 10 90 depending on
the power mode
Acknowledgements I would like to thank my advisor
Diana Marculescu and her graduate student Phillip
Stanley-Marbell, for their invaluable help and
guidance.
Presented By Jianjian Sun Electrical Computer
Engineering, Carnegie Mellon University