SLUSFD7 April   2024 BQ25308

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Description (continued)
  6. 5 Device Comparison Table
  7. 6 Pin Configuration and Functions
  8. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Timing Requirements
    7. 7.7 Typical Characteristics
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Device Power Up
        1. 8.3.1.1 Power-On-Reset (POR)
        2. 8.3.1.2 REGN Regulator Power Up
        3. 8.3.1.3 Charger Power Up
        4. 8.3.1.4 Charger Enable and Disable by EN Pin
        5. 8.3.1.5 Device Unplugged From Input Source
      2. 8.3.2 Battery Charging Management
        1. 8.3.2.1 Battery Charging Profile
        2. 8.3.2.2 Battery Charging Profile for LiFePO4
        3. 8.3.2.3 Precharge
        4. 8.3.2.4 Charging Termination
        5. 8.3.2.5 Battery Recharge
        6. 8.3.2.6 Charging Safety Timer
        7. 8.3.2.7 Thermistor Temperature Monitoring
      3. 8.3.3 Charging Status Indicator (STAT)
      4. 8.3.4 Protections
        1. 8.3.4.1 Voltage and Current Monitoring
          1. 8.3.4.1.1 Input Over-Voltage Protection
          2. 8.3.4.1.2 Input Voltage Dynamic Power Management (VINDPM)
          3. 8.3.4.1.3 Input Current Limit
          4. 8.3.4.1.4 Cycle-by-Cycle Current Limit
        2. 8.3.4.2 Thermal Regulation and Thermal Shutdown
        3. 8.3.4.3 Battery Protection
          1. 8.3.4.3.1 Battery Over-Voltage Protection (VBAT_OVP)
          2. 8.3.4.3.2 Dead Battery Charge Inhibit
        4. 8.3.4.4 ICHG Pin Open and Short Protection
    4. 8.4 Device Functional Modes
      1. 8.4.1 Disable Mode, HiZ Mode, Sleep Mode, Charge Mode, Termination Mode, and Fault Mode
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Typical Application
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Charge Voltage Settings
          2. 9.2.1.2.2 Charge Current Setting
          3. 9.2.1.2.3 Inductor Selection
          4. 9.2.1.2.4 Input Capacitor
          5. 9.2.1.2.5 Output Capacitor
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Typical Application with External Power Path
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
        3. 9.2.2.3 Application Curves
  11. 10Power Supply Recommendations
  12. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  13. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Support Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  14. 13Revision History
  15. 14Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • RTE|16
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.3.4.2 Thermal Regulation and Thermal Shutdown

The device monitors the junction temperature TJ to avoid overheating the chip and limit the device surface temperature. When the internal junction temperature exceeds thermal regulation limit TREG, the device lowers down the charge current. During thermal regulation, the average charging current is usually below the programmed battery charging current. Therefore, termination is disabled and the safety timer runs at half the clock rate.

Additionally, the device has thermal shutdown built in to turn off the charger when device junction temperature exceeds TSHUT rising threshold. The charger is reenabled when the junction temperature is below TSHUT falling threshold. During thermal shutdown, the safety timer stops counting and it resumes when the temperature drops below the threshold.