SLUS937C December   2009  – December 2019 BQ24072T , BQ24075T , BQ24079T

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Simplified Circuit
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Device Options
  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  Undervoltage Lockout (UVLO)
      2. 9.3.2  Overvoltage Protection (OVP)
      3. 9.3.3  Dynamic Power-Path Management
      4. 9.3.4  Battery Charging
      5. 9.3.5  Charge Current Translator
      6. 9.3.6  Battery Detection and Recharge
      7. 9.3.7  Termination Disable (TD Input, BQ24072T)
      8. 9.3.8  Battery Disconnect (SYSOFF Input)
      9. 9.3.9  Dynamic Charge Timers (TMR Input)
      10. 9.3.10 Status Indicators (PGOOD, CHG)
      11. 9.3.11 Thermal Regulation and Thermal Shutdown
      12. 9.3.12 Battery Pack Temperature Monitoring
    4. 9.4 Device Functional Modes
      1. 9.4.1 Input Source Connected (Adapter or USB)
        1. 9.4.1.1 Input DPM Mode (VIN-DPM)
        2. 9.4.1.2 DPPM Mode
        3. 9.4.1.3 Battery Supplement Mode
      2. 9.4.2 Input Source Not Connected
  10. 10Applications and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Applications
      1. 10.2.1 Using the BQ24075T, BQ24079T to Disconnect the Battery from the System
        1. 10.2.1.1 Design Requirements
        2. 10.2.1.2 Detailed Design Procedure
          1. 10.2.1.2.1 Program the Fast Charge Current (ISET):
          2. 10.2.1.2.2 Program the Input Current Limit (ILIM):
          3. 10.2.1.2.3 Program 6.25-hour Fast-Charge Safety Timer (TMR):
          4. 10.2.1.2.4 TS Function:
          5. 10.2.1.2.5 CHG and PGOOD LED Status:
          6. 10.2.1.2.6 Processor Monitoring Status:
          7. 10.2.1.2.7 System ON/OFF (SYSOFF):
          8. 10.2.1.2.8 Selecting IN, OUT and BAT Capacitors
        3. 10.2.1.3 Application Curves
      2. 10.2.2 BQ24072T in a Host Controlled Charger Application
        1. 10.2.2.1 Design Requirements
        2. 10.2.2.2 Detailed Design Procedures
          1. 10.2.2.2.1 Termination Disable:
        3. 10.2.2.3 Application Curves
  11. 11Power Supply Recommendations
    1. 11.1 Power On
      1. 11.1.1 Half-Wave Adapters
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
    3. 12.3 Thermal Package
  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

5 Description (continued)

Additionally, the regulated system input enables instant system turn-on when plugged in even with a totally discharged battery. The power-path management architecture also permits the battery to supplement the system current requirements when the adapter cannot deliver the peak system currents, enabling the use of a smaller adapter.

The battery is charged in three phases: conditioning, constant current, and constant voltage. In all charge phases, an internal control loop monitors the IC junction temperature and reduces the charge current if the internal temperature threshold is exceeded. The charger power stage and charge current sense functions are fully integrated. The charger function has high accuracy current and voltage regulation loops, charge status display, and charge termination. The input current limit and charge current are programmable using external resistors.