Analog Devices MAX8971 Product Info

• 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 (MAX8971EWP+ and MAX8971GEWP+)
    • 4.35V, 4.40V, 4.45V, 4.50V (MAX8971BEWP+)
  • 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 (V_ICHG) for Baseband ADC
• Reverse Battery Leakage Protection
• Input/Output Overvoltage Protection
• Interrupt Status Output

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.

Applications

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