The Maxim Integrated MAX17262 with internal current sensing and MAX17263 with LED control deliver high-accuracy battery state-of-charge information to extend runtime of mobile and portable devices

By Warren Miller, contributing
writer

The challenge
of measuring the state of charge (SOC) of lithium-ion batteries is an issue for
manufacturers of everything from smartphones and wearables to power tools and
electric bikes. Accurately determining the amount of battery charge left in
lithium-ion (Li-ion) batteries can go a long way toward improving their overall
lifespan, reliability, and runtime. Maxim Integrated Products, Inc. recently announced a pair of new
fuel-gauge ICs designed to provide market-leading accuracy of SOC measurements
while decreasing time-to-market issues for manufacturers.

The MAX17262 single-cell and MAX17263 multi-cell fuel-gauge ICs both use the ModelGauge m5 EZ algorithm and
standard coulomb counting to produce high-accuracy SOC measurements without the
need for battery characterization, a costly and time-consuming process.

Key features:

  • Provide
    accurate time-to-empty (1%) and time-to-full state-of-charge data across a
    wide range of load conditions and temperatures
  • The
    ModelGauge m5 EZ algorithm eliminates the battery-characterization and
    calibration process
  • Quiescent
    current of 5.2 µA for the MAX17262 and 8.2 µA for MAX17263 extends runtime
  • Integrated
    Rsense current resistor (voltage and coulomb counting hybrid) reduces
    overall footprint and BOM cost and simplifies board layout
  • At
    1.5 × 1.5 mm, the
    MAX17262 is 30% smaller compared to using a discrete sense resistor with
    an alternate fuel gauge, and at 3 × 3 mm, the MAX17263 is the smallest in
    its class for lithium-ion-powered devices
  • The
    single-/multi-cell MAX17263 also drives LEDs to indicate battery status on
    a pushbutton press or system status on system microcontroller commands

The MAX17262
integrates a Rsense current resistor that eliminates the need to use a larger
discrete part, while the integrated LED controller in the MAX17263 offloads the
functionality from the microcontroller and minimizes battery drain. The
MAX17623 is a more apt solution for applications that don’t include a digital
display, driving anywhere from 3 to 12 LEDs for battery and system status.

 

Both ICs
feature low quiescent current levels (5.2 µA for the MAX17262, the lowest level
in its class, and 8.2 µA for the MAX17263), allowing them to curtail current
loss during extended periods of device standby time, a factor in battery-life
degradation. Both ICs also implement
a dynamic power feature that allows for maximizing system performance without
resulting in a battery shutdown.

The MAX17262
and MAX17263 are priced at $0.95 and $1.49, respectively (1,000 pieces, FOB
USA). Both parts are also available via select authorized distributors.

The MAX17262XEVKIT# and MAX17263GEVKIT# evaluation kits are each priced at $60. Support resources include the
MAX1726x ModelGauge m5 EZ User Guide and Software Implementation Guide as well
as Linux drivers.