SLUS940D September   2009  – May 2021 BQ24050 , BQ24052

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings (1)
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions (1)
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Timing Requirements
    7. 6.7 Switching Characteristics
    8. 6.8 Typical Characteristics
      1. 6.8.1 Power Up, Down, OVP, Disable and Enable Waveforms
      2. 6.8.2 Protection Circuits Waveforms
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Power Down, or Undervoltage Lockout (UVLO)
      2. 7.3.2  Power Up
      3. 7.3.3  D+, D– Detection
      4. 7.3.4  New Charge Cycle
      5. 7.3.5  Overvoltage Protection (OVP) – Continuously Monitored
      6. 7.3.6  CHG Pin Indication
      7. 7.3.7  CHG LED Pullup Source
      8. 7.3.8  Input DPM Mode (VIN-DPM or IN-DPM)
      9. 7.3.9  OUT
      10. 7.3.10 ISET
      11. 7.3.11 TS
      12. 7.3.12 Termination and Timer Disable Mode (TTDM) -TS Pin High
      13. 7.3.13 Timers
      14. 7.3.14 Termination
      15. 7.3.15 Battery Detect Routine
      16. 7.3.16 Refresh Threshold
      17. 7.3.17 Starting a Charge on a Full Battery
    4. 7.4 Device Functional Modes
      1. 7.4.1 Sleep Mode
    5. 7.5 Programming
      1. 7.5.1 PRE_TERM – Precharge and Termination Programmable Threshold
      2. 7.5.2 ISET2
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 BQ2405x Charger Application Design Example
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Program the Fast Charge Current, ISET
          2. 8.2.1.2.2 Program the Termination Current Threshold, ITERM
          3. 8.2.1.2.3 TS Function
          4. 8.2.1.2.4 CHG
          5. 8.2.1.2.5 Selecting IN and OUT Pin Capacitors
        3. 8.2.1.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Thermal Considerations
      1. 10.3.1 Leakage Current Effects on Battery Capacity
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Support Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary

3 Description

The BQ2405x series of devices are highly integrated Li-Ion and Li-Pol linear chargers devices targeted at space-limited portable applications. The devices operate from either a USB port or AC adapter. The high-input voltage range with input overvoltage protection supports low-cost unregulated adapters.

The BQ2405x has a single power output that charges the battery. A system load can be placed in parallel with the battery as long as the average system load does not keep the battery from charging fully during the 10-hour safety timer.

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 an 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 precharge current and termination current threshold are programmed through an external resistor. The fast charge current value is also programmable through an external resistor.

Device Information(1)
PART NUMBERPACKAGEBODY SIZE (NOM)
BQ24050WSON (10)2.00 mm × 2.00 mm
BQ24052
(1) For all available packages, see the orderable addendum at the end of the data sheet.
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