BQ24170RGYR BQ24171RGYR BQ24172RGYR 1.6MHz Usb Lithium Ion Battery Charger Circuit Adjustable Charge

Voltage

1 Features

• 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

• – ±4% Input Current Regulation
• <15-μA Battery Current With Adapter Removed
• <1.5-mA Input Current With Adapter Present and Charge Disabled

2 Applications

• Tablet PCs

• Portable Data Capture Terminals

• Portable Printers

• Medical Diagnostics Equipment

• Battery Bay Chargers

• Battery Backup Systems

3 Description

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.

bq2417

bq2417