Industry's Smallest 1.55A 1-Cell Li+ DC-DC Charger

Switching Charger Delivers High Efficiency (90%~92%)

Please check latest availability status for a specific part variant.


The MAX8971 is a compact, high-frequency, high-efficiency switch-mode charger for a one-cell lithium-ion (Li+) battery. It delivers up to 1.55A of current to the battery from inputs up to 7.5V and withstands transient inputs up to 22V. The 4MHz switch-mode charger is ideally suited for small portable devices, such as Bluetooth® headsets, AR/VR glasses, and other lithium-ion powered accessories. It minimizes component size and heat.

Battery-protection features include: low-voltage prequalification, charge fault timer, die temperature monitoring, and battery temperature monitoring. The battery temperature monitoring adjusts the charge current and termination voltage for safe use of secondary lithium-ion batteries.

The IC accepts either a general DC input or USB. It has programmable automatic input-current limiting to protect upstream charging sources such as USB.

Charge parameters are easily adjustable through an I²C interface. Charge is terminated based on user-selectable minimum current level. Charge status is provided to the application processor through an interrupt pin.

The IC is available in a space-saving, 20-bump, 2.18mm x 1.62mm WLP package.
MAX8971: Simplified Operating Circuit MAX8971: Simplified Operating Circuit Enlarge+

Key Features

  • Switch-Mode Charger
    • High-Efficiency
    • Low Heat
    • Fast Charge Time
  • Small and Simple
  • Precise
    • Up to ±5% Current Regulation and 0.5% Voltage Regulation
  • Safe
    • JEITA Battery Temperature Monitor
    • Over/Undervoltage Protection, Safety Timers, Temperature Regulation
    • USB Friendly
  • Flexible
    • Programmable Voltage/Current
    • Status/Interrupts Through I2C
    • Automatic Input Current Limit
  • I2C Interface
    • Input Current Limit (100mA to 1500mA)
    • Fast-Charge/Termination Current (250mA to 1550mA)
    • Charge Voltage (4.1V, 4.15V, 4.2V, 4.35V)
    • Termination Enable
  • +22V Absolute Maximum Input Voltage Rating
  • Up to 7.5V Maximum Operating Input Voltage
  • 5V USB/Safeout LDO for USB PHY
  • 2.3A GSM RF Test Mode (Factory Testing)
  • Charge Current to Voltage Conversion (VICHG) for Baseband ADC
  • Reverse Battery Leakage Protection
  • Input/Output Overvoltage Protection
  • Interrupt Status Output


  • AR/VR Glasses
  • Bluetooth Headsets
  • Hearables
  • Portable Devices
  • Smartphones
  • USB Charging
  • Wearables

MAX8971EVKIT: Evaluation System for the MAX8971
MAX8971EVMINIQU: Evaluation System for the MAX8971
Product Reliability Reports: MAX8971.pdf 
Device   Fab Process   Technology   Sample size   Rejects   FIT at 25°C   FIT at 55°C   Material Composition  

Note : The failure rates are summarized by technology and mapped to the associated material part numbers. The failure rates are highly dependent on the number of units tested.

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