The MAX17048/MAX17049X+TG075 ICs are tiny, micropower current fuel gauges for lithium-ion (Li+) batteries in handheld and portable equipment. The MAX17048 operates with a single lithium cell and the MAX17049X+TG075 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
- Best of 16 Samples to Estimate Initial SOC
- Programmable Reset for Battery Swap
- 2.28V to 3.48V Range
- Configurable Alert Indicator
- Low SOC
- 1% Change in SOC
- Battery Undervoltage/Overvoltage
- VRESET Alert
- 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
