Description générale

The MAX17261 is an ultra-low power fuel gauge IC which implements the Maxim ModelGauge™ m5 algorithm. The IC monitors a multiple-series cell battery pack with an external resistor divider.

The ModelGauge m5 EZ algorithm makes fuel gauge implementation easy by eliminating battery characterization requirements and simplifying host software interaction. The algorithm provides tolerance against battery diversity for most lithium batteries and applications.

The algorithm combines the short-term accuracy and linearity of a coulomb counter with the long-term stability of a voltage-based fuel gauge, along with temperature compensation to provide industry-leading fuel gauge accuracy. The IC automatically compensates for cell-aging, temperature, discharge rate, and provides accurate state-of charge (SOC) in percentage (%) and remaining capacity in milliampere-hours (mAh) over a wide range of operating conditions. As the battery approaches the critical region near empty, the algorithm invokes a special correction mechanism that eliminates any error. The IC provides accurate estimation of time-to-empty and time-to-full and provides three methods for reporting the age of the battery: reduction in capacity, increase in battery resistance,and cycle odometer.

The IC provides precision measurements of current, voltage, and temperature. The temperature of the battery pack is measured using an internal temperature sensor or external thermistor. A 2-wire I2C interface provides access to data and control registers. The IC is available in a tiny lead-free 0.4mm pitch, 1.5mm x 1.5mm, 9-pin WLP package and 3mm x 3mm, 14-pin TDFN package.

 

Applications

Tablets, 2-in-1 Laptops

Digital Still, Video, and Action Cameras

Dispositifs médicaux

Handheld Computers and Terminals

Financial Terminals

Mobile Printers

Augmented/Virtual Reality Devices

Robots

E-Bikes

Battery Backups

Wireless Speakers

 

Avantages et caractéristiques

ModelGauge m5 EZ

No Characterization Required for EZ Performance

Robust Against Battery Variation

Eliminates Error Near Empty Voltage

Eliminates Coulomb Counter Drift

Compensates for Age, Current, and Temperature

Does Not Require Empty, Full, or Idle States

Low 5.1μA Operating Current

Monitors Multiple-Cell Battery Pack

Wide Sense Resistor Range: 1mΩ to 1000mΩ

PCB Metal Sensing + Temperature Compensation

Supports Li+ and Variants Including LiFePO4

Thermistor or ±1°C Internal Temperature

Dynamic Power Estimates Power Capability During Discharge

Time-to-Empty and Time-to-Full Estimation

Predicts Remaining Capacity Under Theoretical Load

No Calibration Required

Alert Indicator for Voltage, SOC, Temperature,Current and 1% SOC Change

 

Description détaillée

The MAX17261 is an ultra-low power fuel gauge IC which implements the Maxim ModelGauge m5 EZ algorithm. The IC measures voltage, current, and temperature accurately to produce fuel gauge results. The ModelGauge m5 EZ robust algorithm provides tolerance against battery diversity. This additional robustness enables simpler implementation for most applications and batteries by avoiding time-consuming battery characterization.

The ModelGauge m5 algorithm combines the short-term accuracy and linearity of a coulomb-counter with the long-term stability of a voltage-based fuel gauge, along with temperature compensation to provide industry-leading fuel gauge accuracy. The IC automatically compensates for aging, temperature, and discharge rate and provides accurate state of charge (SOC) in percentage (%) and remaining capacity in milliampere-hours (mAhr) over a wide range of operating conditions. Fuel gauge error always converges to 0% as the cell approaches empty.

The IC has a register set that is compatible with Intel’s DBPT v2 dynamic power standard. This allows the system designer to safely estimate the maximum allowed CPU turbo-boost power level in complex power conditions. The IC provides accurate estimation of time-to-empty and time-to-full and provides three methods for reporting the age of the battery: reduction in capacity, increase in battery resistance, and cycle odometer.

The IC contains a unique serial number. It can be used for cloud-based authentication.

Communication to the host occurs over standard I2C interface.