SLUSAD2C November 2010 – April 2015
PRODUCTION DATA.
- 1 Features
- 2 Applications
- 3 Description
- 4 Revision History
- 5 Description (continued)
- 6 Device Comparison Table
- 7 Pin Configuration and Functions
- 8 Specifications
-
9 Detailed Description
- 9.1 Overview
- 9.2 Functional Block Diagram
- 9.3
Feature Description
- 9.3.1 Battery Voltage Regulation
- 9.3.2 Battery Current Regulation
- 9.3.3 Battery Precharge Current Regulation
- 9.3.4 Input Current Regulation
- 9.3.5 Charge Termination, Recharge, and Safety Timers
- 9.3.6 Power Up
- 9.3.7 Input Undervoltage Lockout (UVLO)
- 9.3.8 Input Overvoltage/Undervoltage Protection
- 9.3.9 Enable and Disable Charging
- 9.3.10 System Power Selector
- 9.3.11 Converter Operation
- 9.3.12 Automatic Internal Soft-Start Charger Current
- 9.3.13 Charge Overcurrent Protection
- 9.3.14 Charge Undercurrent Protection
- 9.3.15 Battery Detection
- 9.3.16 Battery Short Protection
- 9.3.17 Battery Overvoltage Protection
- 9.3.18 Temperature Qualification
- 9.3.19 MOSFET Short Circuit and Inductor Short Circuit Protection
- 9.3.20 Thermal Regulation and Shutdown Protection
- 9.3.21 Timer Fault Recovery
- 9.3.22 Inductor, Capacitor, and Sense Resistor Selection Guidelines
- 9.3.23 Charge Status Outputs
- 9.4 Device Functional Modes
- 10Application and Implementation
- 11Power Supply Recommendations
- 12Layout
- 13Device and Documentation Support
- 14Mechanical, Packaging, and Orderable Information
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
- ±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
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.
Device Information(1)
| PART NUMBER | PACKAGE | BODY SIZE (NOM) |
|---|---|---|
| bq24170 | VQFN (24) | 5.50 mm × 3.50 mm |
| bq24172 |
- For all available packages, see the orderable addendum at the end of the data sheet.
Typical Application Schematic
