SLUSAD2C November   2010  – April 2015 BQ24170 , BQ24172

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Device Comparison Table
  7. 7 Pin Configuration and Functions
  8. 8 Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 Typical Characteristics
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  Battery Voltage Regulation
      2. 9.3.2  Battery Current Regulation
      3. 9.3.3  Battery Precharge Current Regulation
      4. 9.3.4  Input Current Regulation
      5. 9.3.5  Charge Termination, Recharge, and Safety Timers
      6. 9.3.6  Power Up
      7. 9.3.7  Input Undervoltage Lockout (UVLO)
      8. 9.3.8  Input Overvoltage/Undervoltage Protection
      9. 9.3.9  Enable and Disable Charging
      10. 9.3.10 System Power Selector
      11. 9.3.11 Converter Operation
      12. 9.3.12 Automatic Internal Soft-Start Charger Current
      13. 9.3.13 Charge Overcurrent Protection
      14. 9.3.14 Charge Undercurrent Protection
      15. 9.3.15 Battery Detection
        1. 9.3.15.1 Example
      16. 9.3.16 Battery Short Protection
      17. 9.3.17 Battery Overvoltage Protection
      18. 9.3.18 Temperature Qualification
      19. 9.3.19 MOSFET Short Circuit and Inductor Short Circuit Protection
      20. 9.3.20 Thermal Regulation and Shutdown Protection
      21. 9.3.21 Timer Fault Recovery
      22. 9.3.22 Inductor, Capacitor, and Sense Resistor Selection Guidelines
      23. 9.3.23 Charge Status Outputs
    4. 9.4 Device Functional Modes
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Inductor Selection
        2. 10.2.2.2 Input Capacitor
        3. 10.2.2.3 Output Capacitor
        4. 10.2.2.4 Input Filter Design
        5. 10.2.2.5 Input ACFET and RBFET Selection
      3. 10.2.3 Application Curve
    3. 10.3 System Examples
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Examples
  13. 13Device and Documentation Support
    1. 13.1 Related Links
    2. 13.2 Trademarks
    3. 13.3 Electrostatic Discharge Caution
    4. 13.4 Glossary
  14. 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
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Typical Application Schematic

bq24170 bq24172 typ_app1_slusad2.gif