• USB-Friendly 4.7-V to 28-V Input Operating Range
• Stand-Alone Charge Controller to Support 1 to 6 Li-Ion or Li-Polymer Battery Cells
• Up to 10-A Charge Current and Adapter Current
• 600-kHz NMOS-NMOS Synchronous Buck Converter
• High-Accuracy Voltage and Current Regulation
  • ±0.5% Charge Voltage Accuracy
  • ±3% Charge Current Accuracy
  • ±3% Adapter Current Accuracy
• Integration
  • Automatic System Power Selection From Adapter or Battery
  • Internal Loop Compensation
  • Internal Soft Start
  • Dynamic Power Management
• Safety Protection
  • Input Overvoltage Protection
  • Battery Thermistor Sense Hot/Cold Charge Suspend
  • Battery Detection
  • Reverse-Protection Input FET
  • Programmable Safety Timer
  • Charge Overcurrent Protection
  • Battery Short Protection
  • Battery Overvoltage Protection
  • Thermal Shutdown
• Status Outputs
  • Adapter Present
  • Charger Operation Status
• Charge Enable Pin
• 6-V Gate Drive for Synchronous Buck Converter
• 30-ns Driver Dead-Time and 99.5% Maximum Effective Duty Cycle
• Energy Star Low Quiescent Current Iq
  • < 15-µA Off-State Battery Discharge Current
  • < 1.5-mA Off-State Input Quiescent Current

• Tablet PCs
• Smart Phones
• Portable Media Players, Navigation Devices, Notebooks and Ultra-Mobile PCs
• Personal Digital Assistants
• Handheld Terminals
• Industrial and Medical Equipment

The bq24618 device is highly integrated Li-ion or Li-polymer switched-mode battery-charge controller. The bq24618 offers a constant-frequency synchronous switching PWM controller with high-accuracy charge current and voltage regulation, charge preconditioning, termination, adapter current regulation and charge status monitoring.

The bq24618 operates from either a USB port or AC adapter and supports charge currents up to 10 A. The device charges the battery in three phases: preconditioning, constant current, and constant voltage. Charge is terminated when the current reaches a minimum user-selectable level. A programmable charge timer provides a safety backup for charge termination. The bq24618 automatically restarts the charge cycle if the battery voltage falls below an internal threshold, and enters a low-quiescent current sleep mode when the input voltage falls below the battery voltage.