TI Power Management Fuel Gauge Accurately Predicts Battery Life in Smart Phones and Other Handhelds

TI Power Management Fuel Gauge Accurately Predicts Battery Life in Smart Phones and Other Handhelds

September 24, 2007

System-Side Impedance Track(TM) Battery Fuel Gauge IC
Enables Single-Cell, Li-Ion Powered Applications to Run
Smarter and Longer


    DALLAS, Sept. 24 /Xinhua-PRNewswire/ -- How much
battery life do I really have left? Texas Instruments
Incorporated (TI) (NYSE: TXN) answers the question by
introducing its system-side fuel gauge integrated circuit
(IC) with Impedance Track(TM) technology for smart phones
and other handhelds. The 2.5 mm x 4 mm gauge predicts
battery life with 99-percent accuracy to extend run-time,
protect data and provide a better user experience for
mobile handheld users.  See: http://www.ti.com/bq27500-pr .
   

    (Logo:
http://www.xprn.com/xprn/sa/20061107170439-20-min.jpg )

    "As mobile devices add more functionality, such as
high-definition video and data transmission, consumers want
to operate their devices just like notebook computers and
expect to know remaining battery capacity," said Dave
Heacock, senior vice president of TI's high-volume analog
and logic business. "Today's announcement builds on
TI's innovative battery fuel gauge technology, which is
used in millions of notebook computers. Our portable device
customers asked to incorporate the technology into their
mobile designs -- and now they can."

    The bq27500 system-side battery fuel gauge with TI's
patented Impedance Track technology accurately measures
data from a device's single-cell Li-Ion battery to predict
remaining battery capacity under all conditions, even as a
battery ages. The tiny IC analyzes precise state-of-charge
by correlating between a battery's voltage and cell
impedance, or resistance, and its current integration to
adjust remaining state-of-charge up or down the predicted
discharge curve.

    Most handhelds today do not accurately gauge remaining
battery capacity, but simply measure the cell voltage to
guess the capacity. Traditional gauging techniques used in
some handhelds require static and unreliable modeling
methods that attempt to compensate for discharge rate,
temperature and age of the cell, and must also model
self-discharge and other non-measurable currents. Since
these models have an inherent error, which is difficult to
minimize, an end-user will not accurately know how much
run-time remains as the battery ages.

    Predicting Remaining Capacity 

    The bq27500 directly measures the effect of a battery's
discharge rate, temperature, age and other factors to
accurately predict remaining life within one percent error.
By measuring and storing real-time battery impedance values,
the IC automatically adjusts to changes in full capacity as
a battery ages. State-of-charge and full capacity are
calculated from the voltage and impedance measurements,
eliminating the need to re-learn from a charge and
discharge cycle.      

    Intelligent Power Optimization 

    As handheld systems provide more functions, the need
has grown for accurate fuel gauging to intelligently manage
available power, alert the user of system operating-time,
and extend the run-time of the system as far as possible.
Accurate battery data is used by applications processors,
such as TI's OMAP3410 processor with SmartReflex(TM) power
and performance technologies, to optimize the system's
complete mobile power operating system. For instance, the
system can leverage low-power modes, clock gating, clock
throttling and dynamic voltage and frequency scaling
capabilities based on battery capacity. The bq27500
provides an accurate reserve energy warning, which allows a
system to save data to non-volatile memory at the end of a
battery's discharge, so work is not lost when battery life
runs out.

    System-Side Implementation

    The bq27500 is implemented on the host system's board,
and can support an embedded or removable battery.
System-side implementation allows a handheld manufacturer
to save cost by designing an end-equipment that does not
need extra electronics added to the battery pack. As
batteries continue to shrink in size, integration of
electronics on the battery becomes more of a challenge.
System-side implementation of the bq27500 can control and
manage other main battery management functions, such as
battery pack authentication. 

    Pricing and Availability

    The bq27500 is available today in volume from TI and
its authorized distributors. Available in a space-saving
12-pin, 2.5 mm x 4 mm SON package, the device's suggested
retail pricing is $1.35 in 1,000-piece quantities.
Evaluation modules of the bq27500, design application
notes, user guides and TI's software design tool are
available through http://power.ti.com . 

    Comprehensive Battery Management Portfolio

    TI provides high-performance battery power management
products for any single-cell or multi-cell battery powered
design, including a full range of battery fuel gauges,
battery charge management, and battery protection and
authentication solutions. The bq20z90 and bq20z70
multi-cell battery fuel gauges target notebook computers
and portable industrial applications. TI's bq27000 family
of fuel gauge ICs supports single-cell battery packs. For
more information on TI's battery management products, see:
http://www.ti.com/battman . 	

    About Texas Instruments

    Texas Instruments Incorporated provides innovative DSP
and analog technologies to meet our customers' real world
signal processing requirements.  In addition to
Semiconductor, the company includes the Education
Technology business.  TI is headquartered in Dallas, Texas,
and has manufacturing, design or sales operations in more
than 25 countries.
    
    Texas Instruments is traded on the New York Stock
Exchange under the symbol TXN.  More information is located
on the World Wide Web at:  http://www.ti.com .

    Please refer all reader inquiries to:

      Texas Instruments Incorporated 
      Semiconductor Group, SC-07142
      Literature Response Center
      14950 FAA Blvd.
      Ft. Worth, TX 76155
      [phone]

    Trademarks

    Impedance Track and OMAP are trademarks of Texas
Instruments.  All other trademarks and registered
trademarks are the property of their respective owners.


    For more information, please contact:

     Matt McKinney
     Texas Instruments
     Tel:   [phone]
     Email: [e-mail]

     Jacqi Moore
     Golin/Harris
     Tel:   [phone]
     Email: [e-mail]