LTC2941-1_15 Datasheet, PDF (1/16 Pages) Linear Technology – 1A I2C Battery Gas Gauge with Internal Sense Resistor

Features
n _{Indicates Accumulated Battery Charge and}
Discharge
n _SMBus/I²_{C Interface}
n _{Integrated 50mΩ High Side Sense Resistor}
n _{±1A Sense Current Range}
n _{High Accuracy Analog Integration}
n _{1% Charge Accuracy}
n _{Configurable Alert Output/Charge Complete Input}
n _{2.7V to 5.5V Operating Range}
n _{Quiescent Current Less than 100µA}
n _{Small 6-Pin 2mm × 3mm DFN package}
Applications
n _{Low Power Handheld Products}
n _{Cellular Phones}
n _{MP3 Player}
n _Cameras
n _GPS
LTC2941-1
1A I²C Battery Gas Gauge
with Internal Sense Resistor
Description
The LTC^®2941-1 measures battery charge state in battery-
powered handheld PC and portable product applications.
Its operating range is perfectly suited for single cell Li-Ion
batteries. A precision coulomb counter integrates current
through an internal sense resistor between the battery’s
positive terminal and the load or charger. The measured
charge is stored in internal registers. An SMBus/I²C in-
terface accesses and configures the device.
The LTC2941-1 features programmable high and low
thresholds for accumulated charge. If a threshold is ex-
ceeded, the device communicates an alert using either the
SMBus alert protocol or by setting a flag in the internal
status register.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and Hot
Swap, ThinSOT and Bat-Track are trademarks of Linear Technology Corporation. All other
trademarks are the property of their respective owners.
Typical Application
CHARGER
I²C/SMBus
TO HOST
SENSE⁺
LTC2941-1
AL/CC
SDA
SENSE^–
SCL
GND
LOAD
0.1µF
+ _1-CELL
Li-Ion
29411 TA01a
Total Charge Error vs Sense Current
1.00
V_SENSE+ = 3.6V
0.75
0.50
0.25
0
–0.25
–0.50
–0.75
–1.00
1
10
100
|I_SENSE| (mA)
1000
29411 TA01b
29411f