• 300-kHz NMOS-NMOS Synchronous Buck Converter
• Stand-Alone Charger Designed Specifically for Lithium Phosphate
• 5-V to 28-V VCC Operating Range, Supports 1 to 7 Battery Cells
• High-Accuracy Voltage and Current Regulation
  • ±0.5% Charge Voltage Accuracy
  • ±3% Charge Current Accuracy
• Integration
  • Internal Loop Compensation
  • Internal Soft Start
• Safety
  • Input Overvoltage Protection
  • Battery Thermistor Sense Suspend Charge at Hot/Cold Charge Suspend and Automatically ICHARGE/8 at WARM/COOL
  • Battery Detection
  • Built-In 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 99.95% Maximum Effective Duty Cycle
• 16-Pin 3.5-mm × 3.5-mm QFN Package
• Energy Star Low Iq
  • < 15-μA Off-State Battery Discharge Current
  • < 1.5-mA Off-State Input Quiescent Current

• Power Tools and Portable Equipment
• Personal Digital Assistants
• Handheld Terminals
• Industrial and Medical Equipment
• Netbooks, Mobile Internet Devices, and Ultramobile PCs

The bq24620 device is a highly integrated lithium phosphate switched-mode battery charge controller. The device offers a constant-frequency synchronous switching PWM controller with high-accuracy charge current and voltage regulation, charge preconditioning, termination, and charge status monitoring.

The bq24620 charges the battery in three phases: preconditioning, constant current, and constant voltage.