STC3105IQT Datasheet, PDF (1/23 Pages) STMicroelectronics – Battery monitor IC with alarm output for gas gauge applications

STC3105
Battery monitor IC with alarm output for gas gauge applications
Features
■ 0.5% accuracy battery voltage monitoring
■ Low battery alarm output with programmable
thresholds
■ Low power: 60 µA in power-saving mode, 2 µA
max in standby mode
■ Ideal for implementation of robust gas gauge
systems using open-circuit voltage and
coulomb counter methods
■ Small 3x2 mm package
Applications
■ Mobile phones, multimedia players, digital
cameras
■ Portable medical equipment
Description
The STC3105 battery monitor includes the
hardware functions required to implement a low-
cost gas gauge for battery monitoring. The
STC3105 uses accurate measurements of the
battery voltage to estimate a battery’s state-of-
charge (SOC). It uses a low cost sense resistor to
precisely sense the charge or discharge states,
detect light-load conditions without ambiguity for
voltage measurements, and accurate SOC
calculation. The coulomb counter method is used
for SOC tracking in high-load conditions.
An alarm output signals a low SOC condition, and
can also indicate low battery voltage. The alarm
threshold levels are programmable.
The device is programmable through an I²C
interface.
TDFN8 3x2
(Plastic micropackage)
Pin connections
(top view)
ALM ¹
SDA ²
SCL ³
GND ⁴
8 _VIN
7 VCC
6 _NC
5 _CG
September 2011
Doc ID 022198 Rev 1
1/23
www.st.com
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