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

9.3.2 Battery Current Regulation

The ISET1 input sets the maximum fast-charging current. Battery charge current is sensed by resistor RSR connected between SRP and SRN. The full-scale differential voltage between SRP and SRN is 100 mV. Thus, for a 10-mΩ sense resistor, the maximum charging current is 10 A. The equation for charge current is:

Equation 2. BQ24610 BQ24617 eq2_ichg_lus892.gif

VISET1, the input voltage range of ISET1, is from 0 V to 2 V. The SRP and SRN pins are used to sense voltage across RSR with default value of 10 mΩ. However, resistors of other values can also be used. A larger sense resistor gives a larger sense voltage and a higher regulation accuracy, but at the expense of higher conduction loss.