• 1.6-MHz Synchronous Switched-Mode Charger with 4-A Integrated N-MOSFETs
• Up to 94% Efficiency
• 30-V Input Rating with Adjustable Overvoltage Protection
  • 4.5-V to 17-V Input Operating Voltage Range
• Battery Charge Voltage
  • bq24170: 1-, 2-, or 3-Cell with 4.2 V/Cell
  • bq24172: Adjustable Charge Voltage
• High Integration
  • Automatic Power Path Selector Between Adapter and Battery
  • Dynamic Power Management
  • Integrated 20-V Switching MOSFETs
  • Integrated Bootstrap Diode
  • Internal Digital Soft Start
• Safety
  • Thermal Regulation Loop Throttles Back Current to Limit TJ = 120°C
  • Thermal Shutdown
  • Battery Thermistor Sense Hot/Cold Charge Suspend and Battery Detect
  • Adjustable Input Overvoltage Protection
  • Cycle-by-Cycle Current Limit
• Accuracy
  • ±0.5% Charge Voltage Regulation
  • ±4% Charge Current Regulation
  • ±4% Input Current Regulation
• <15-μA Battery Current With Adapter Removed
• <1.5-mA Input Current With Adapter Present and Charge Disabled

• Tablet PCs
• Portable Data Capture Terminals
• Portable Printers
• Medical Diagnostics Equipment
• Battery Bay Chargers
• Battery Backup Systems

The bq2417x device is a highly integrated stand-alone Li-Ion and Li-Polymer switched-mode battery charger with two integrated N-channel power MOSFETs. The device offers a constant-frequency synchronous PWM controller with high-accuracy regulation of input current, charge current, and voltage. The bq2417x closely monitors the battery pack temperature to allow charge only in a preset temperature window. The bq24170 charges one, two, or three cells (selected by CELL pin), and the bq24172 is adjustable for up to three series Li+ cells.