Dual Input, Power Path, 3A Switching Mode Charger with Fuel Gauge

Industry's Highest Efficiency Switching Mode Charger in a Smaller Solution Size in 3.87mm x 3.61mm WLP

Please check latest availability status for a specific part variant.


The MAX77818 integrates a high-performance 3A switching charger and proprietary ModelGauge™ m5 fuel gauge in a space saving WLP package, ideal for USB powered portable devices. The smart power path charger supports two inputs with reverse blocking and USB On-the-Go (OTG), integrates all power switches, operates at high-switching frequency with high efficiency, enabling low heat designs with small external components. The ModelGauge m5 algorithm combines the excellent 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 device also integrates two high voltage input LDOs and is highly programmable with I2C interface.

MAX77818: Simplified Functional Diagram MAX77818: Simplified Functional Diagram Enlarge+

Key Features

  • Smart Power Path, Dual Input Switching Charger
    • Up to 13.4V Operating/16V Withstand/4A (CHGIN)
    • Up to 6V Operating/1.26A (WCIN)
    • Reverse Leakage Blocking
    • Reverse Boost with up to 5.1V/1.5A (OTG)
    • Integrated Low-Loss FETs for 3A Charging/4.5A Discharging
    • 95.6% Peak Efficiency at 5V/4.35V
    • Full Feature Charger with Protection
    • Thermal Regulation and JEITA Compliance
  • ModelGauge m5 Fuel Gauge
    • Time-to-Empty and Time-to-Full Prediction
    • Accurate Battery Capacity (SOC) and Time-to-Empty Readings
      • Temperature, Age, and Discharge Rate Compensated
      • No Calibration
      • Integrated FET Current Sensing
      • Maintains Accuracy without Empty, Full, or Idle States
    • Low Quiescent Current (IQ)
  • Two High Voltage Input LDOs
  • I2C Serial Interface
  • 72-Bump, 3.867mm x 3.608mm, 0.4mm Pitch WLP


  • Bluetooth Headsets
  • Handheld Devices
  • Industrial PCs
  • Internet of Things (IoT)
  • Portable Medical Devices
  • Smart Home Automation, Sensors
  • Wearable, Smart Watches
  • Wireless Speakers

See parametric specs for Battery Chargers (74)

Part NumberLithium Ion CellsProtected VIN
Charging VIN
Charge Rate Set byMax. ICHG
Charge TerminationCharge RegulationOper. Temp.
maxmaxSee Notes
MAX77818 11614I2C/SMBus3
Min. Charge Current
Switchmode-40 to +85
$2.05 @1k

Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

MAX77818EVSYS: Evaluation System for MAX77818
Product Reliability Reports: MAX77818.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.

Quality Management System >
Environmental Management System >


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