The MAX17048/MAX17049 ICs are tiny, micropower current fuel gauges for lithium-ion (Li+) batteries in handheld and portable equipment. The MAX17048G+T10 operates with a single lithium cell and the MAX17049 with two lithium cells in series.
The ICs use the sophisticated Li+ battery-modeling algorithm ModelGauge to track the battery relative state-of-charge (SOC) continuously over widely varying charge and discharge conditions. The ModelGauge algorithm eliminates current-sense resistor and battery-learn cycles required in traditional fuel gauges. Temperature compensation is implemented using the system microcontroller.
The ICs automatically detect when the battery enters a low-current state and switches into a low-power 3μA hibernate mode, while still providing accurate fuel gauging. The ICs automatically exit hibernate mode when the system returns to active state.
On battery insertion, the ICs debounce initial voltage measurements to improve the initial SOC estimate, thus allowing them to be located on system side. SOC, voltage, and rate information is accessed using the I2C interface. The ICs are available in a tiny 0.9mm × 1.7mm, 8-bump wafer-level package (WLP), or a 2mm × 2mm, 8-pin TDFN package.
Feature
MAX17048: 1 Cell, MAX17049: 2 Cells
Precision ±7.5m-V/Cell Voltage Measurement
ModelGauge Algorithm
Provides Accurate State-of-Charge
Compensates for Temperature/Load Variation
Does Not Accumulate Errors, Unlike Coulomb Counters
Eliminates Learning
Eliminates Current-Sense Resistor
Ultra-Low Quiescent Current
3μA Hibernate, 23μA Active
Fuel Gauges in Hibernate Mode
Automatically Enters and Exits Hibernate Mode
Reports Charge and Discharge Rate
Battery-Insertion Debounce
Programmable Reset for Battery Swap
Configurable Alert Indicator
I2C Interface
8-Bit OTP ID Register (Contact Factory)
Applications
Bluetooth Headsets
Digital Still, Video, and Action Cameras
Handheld Computers and Terminals
Health and Fitness Monitors
Home and Building Automation, Sensors
Medical Devices
Smartphones, Tablets
Smartwatches, Wearables
Wireless Speakers