SLUS892D December   2009  – December 2019 BQ24610 , BQ24617

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Device Comparison Table
  7. 7 Pin Configuration and Functions
    1.     Pin 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  Input Adapter Current Regulation
      4. 9.3.4  Precharge
      5. 9.3.5  Charge Termination, Recharge, and Safety Timer
      6. 9.3.6  Power Up
      7. 9.3.7  Enable and Disable Charging
      8. 9.3.8  System Power Selector
      9. 9.3.9  Automatic Internal Soft-Start Charger Current
      10. 9.3.10 Converter Operation
      11. 9.3.11 Synchronous and Nonsynchronous Operation
      12. 9.3.12 Cycle-by-Cycle Charge Undercurrent Protection
      13. 9.3.13 Input Overvoltage Protection (ACOV)
      14. 9.3.14 Input Undervoltage Lockout (UVLO)
      15. 9.3.15 Battery Overvoltage Protection
      16. 9.3.16 Cycle-by-Cycle Charge Overcurrent Protection
      17. 9.3.17 Thermal Shutdown Protection
      18. 9.3.18 Temperature Qualification
      19. 9.3.19 Timer Fault Recovery
      20. 9.3.20 PG Output
      21. 9.3.21 CE (Charge Enable)
      22. 9.3.22 Charge Status Outputs
      23. 9.3.23 Battery Detection
    4. 9.4 Device Functional Modes
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Applications
      1. 10.2.1 System with Power Path
        1. 10.2.1.1 Design Requirements
        2. 10.2.1.2 Detailed Design Procedure
          1. 10.2.1.2.1 Inductor Selection
          2. 10.2.1.2.2 Input Capacitor
          3. 10.2.1.2.3 Output Capacitor
          4. 10.2.1.2.4 Power MOSFETs Selection
          5. 10.2.1.2.5 Input Filter Design
          6. 10.2.1.2.6 Inductor, Capacitor, and Sense Resistor Selection Guidelines
        3. 10.2.1.3 Application Curves
      2. 10.2.2 Simplified System without Power Path or DPM
        1. 10.2.2.1 Design Requirements
        2. 10.2.2.2 Detailed Design Procedure
        3. 10.2.2.3 Application Curves
      3. 10.2.3 Lead-Acid Charging System
        1. 10.2.3.1 Design Requirements
        2. 10.2.3.2 Detailed Design Procedure
        3. 10.2.3.3 Application Curves
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Device Support
      1. 13.1.1 Third-Party Products Disclaimer
    2. 13.2 Related Links
    3. 13.3 Receiving Notification of Documentation Updates
    4. 13.4 Support Resources
    5. 13.5 Trademarks
    6. 13.6 Electrostatic Discharge Caution
    7. 13.7 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

9.1 Overview

The BQ2461x device is a stand-alone, integrated Li-ion or Li-polymer battery charger. The device employs a switched-mode synchronous buck PWM controller with constant switching frequency. The device controls external switches to prevent battery discharge back to the input, connect the adapter to the system, and connect the battery to the system using 6-V gate drives for better system efficiency. The BQ2461x features Dynamic Power Management (DPM) which reduces battery charge current when the input power limit is reached to avoid overloading the AC adapter when supplying current to the system and the battery charger simultaneously. A highly accurate current-sense amplifier enables precise measurement of input current from the AC adapter to monitor the overall system power. The input current limit can be configured through the ACSET pin of the device.

The BQ2461x has a battery detect scheme that allows it to automatically detect the presence and absence of a battery. When the battery is detected, charging begins in one of three phases (depending upon battery voltage): precharge, constant current (fast-charge current regulation), and constant voltage (fast-charge voltage regulation). The device will terminate charging when the termination current threshold has been reached and will begin a recharge cycle when the battery voltage has dropped below the recharge threshold (VRECHG). Precharge, constant current, and termination current can be configured through the ISET1 and ISET2 pins, allowing for flexibility in battery charging profile. During charging, the integrated fault monitors of the device, such as battery overvoltage protection, battery short detection (VBATSHT), thermal shutdown (internal TSHUT and TS pin), safety timer expiration (TTC pin), and input voltage protection (VACOV), ensure battery safety.

The BQ2461x has three status pins (STAT1, STAT2, and PG) to indicate the charging status and input voltage (AC adapter) status. These pins can be used to drive LEDs or communicate with a host processor.

BQ24610 BQ24617 profile_lus892.gifFigure 14. Typical Charging Profile