SLUS805C April 2008  – August 2015

PRODUCTION DATA. 

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  6. Specifications
    1. 6.1Absolute Maximum Ratings
    2. 6.2ESD Ratings
    3. 6.3Recommended Operating Conditions
    4. 6.4Thermal Information
    5. 6.5Electrical Characteristics
    6. 6.6Timing Requirements
    7. 6.7Typical Characteristics
  7. Detailed Description
    1. 7.1Overview
    2. 7.2Functional Block Diagram
    3. 7.3Feature Description
      1. 7.3.1Input Overvoltage Protection
      2. 7.3.2Battery Overvoltage Protection
      3. 7.3.3Thermal Protection
      4. 7.3.4Start-Up Short-Circuit Protection
      5. 7.3.5Enable Function
      6. 7.3.6Fault Indication
    4. 7.4Device Functional Modes
      1. 7.4.1OPERATION Mode
      2. 7.4.2POWER-DOWN Mode
      3. 7.4.3POWER-ON RESET Mode
  8. Application and Implementation
    1. 8.1Application Information
    2. 8.2Typical Application
      1. 8.2.1Design Requirements
      2. 8.2.2Detailed Design Procedure
        1. 8.2.2.1Selection of R(BAT)
        2. 8.2.2.2Selection of R(CE)
        3. 8.2.2.3Selection of Input and Output Bypass Capacitors
      3. 8.2.3Application Curves
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1Layout Guidelines
    2. 10.2Layout Example
  11. 11Device and Documentation Support
    1. 11.1Related Links
    2. 11.2Community Resources
    3. 11.3Trademarks
    4. 11.4Electrostatic Discharge Caution
    5. 11.5Glossary
  12. 12Mechanical, Packaging, and Orderable Information

1 Features

  • Input Overvoltage Protection
  • Accurate Battery Overvoltage Protection
  • Output Short-Circuit Protection
  • Soft-Start to Prevent Inrush Currents
  • Soft-Stop to Prevent Voltage Spikes
  • Maximum Input Voltage of 30 V
  • Supports up to 1.7-A Load Current
  • Thermal Shutdown
  • Enable Function
  • Fault Status Indication
  • Small 2 mm × 2 mm 8-Pin WSON Package

2 Applications

  • Smart Phones, Mobile Phones
  • PDAs
  • MP3 Players
  • Low-Power Handheld Devices

3 Description

The bq2438x family of devices are charger front-end integrated circuits (ICs) designed to provide protection to Li-ion batteries from failures of the charging circuit. The device continuously monitors the input voltage and battery voltage. The device operates like a linear regulator, maintaining a 5.5-V (bq24380) or 5-V (bq24381, bq24382) output with input voltages up to the Input overvoltage threshold. During input overvoltage conditions, the device immediately turns off the internal pass FET disconnecting the charging circuit from the damaging input source. Additionally, if the battery voltage rises to unsafe levels while charging, power is removed from the system. The device checks for short-circuit or overload conditions at its output when turning the pass FET on, and if it finds unsafe conditions, it switches off and then rechecks the conditions. Additionally, the device also monitors its die temperature and switches off if it exceeds 140°C.

When the device is controlled by a processor, the device provides status information about fault conditions to the host.

Device Information(1)

PART NUMBERPACKAGEBODY SIZE (NOM)
bq24380WSON (8)2.00 mm × 2.00 mm
bq24381
bq24382
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Simplified Schematic

bq24380 bq24381 bq24382 app_sch_lus805.gif