SLUS784E December   2007  – December 2015

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Device Options
  6. Pin Configuration and Functions
  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 Dissipation Ratings
    8. 7.8 Typical Characteristics
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Control Logic Overview
      2. 8.3.2  Temperature Qualification (Applies Only to Versions With TS Pin Option)
      3. 8.3.3  Input Overvoltage Detection, Power Good Status Output
      4. 8.3.4  Charge Status Outputs
      5. 8.3.5  Battery Charging: Constant Current Phase
      6. 8.3.6  Charge Current Translator
      7. 8.3.7  Battery Voltage Regulation
      8. 8.3.8  Pre-Charge Timer
      9. 8.3.9  Thermal Protection Loop
      10. 8.3.10 Thermal Shutdown And Protection
      11. 8.3.11 Dynamic Timer Function
      12. 8.3.12 Charge Termination Detection and Recharge
      13. 8.3.13 Battery Absent Detection - Voltage Mode Algorithm
      14. 8.3.14 Charge Safety Timer
      15. 8.3.15 Short-Circuit Protection
      16. 8.3.16 Startup With Deeply Depleted Battery Connected
    4. 8.4 Device Functional Modes
      1. 8.4.1 Power Down
      2. 8.4.2 Sleep Mode
      3. 8.4.3 Overvoltage Lockout
      4. 8.4.4 Stand-By Mode
      5. 8.4.5 Begin Charge Mode
      6. 8.4.6 Charging Mode
      7. 8.4.7 Suspend Mode
      8. 8.4.8 LDO Mode Operation
      9. 8.4.9 State Machine Diagram
  9. Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 bq24086 and bq24088 Typical Application
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Selecting Input and Output Capacitor
          2. 9.2.1.2.2 Using Adapters With Large Output Voltage Ripple
          3. 9.2.1.2.3 Calculations
        3. 9.2.1.3 Application Curves
      2. 9.2.2 bq24085 Typical Application
        1. 9.2.2.1 Design Requirements
      3. 9.2.3 bq24087 Typical Application
        1. 9.2.3.1 Design Requirements
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
    3. 11.3 Thermal Considerations
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Related Links
    3. 12.3 Community Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • DRC|10
Thermal pad, mechanical data (Package|Pins)
Orderable Information

1 Features

  • Ideal for Low-Dropout Designs for Single-Cell Li-Ion or Li-Pol Packs in Space Limited Applications
  • Integrated Power FET and Current Sensor for up to 750-mA Charge Applications
  • Reverse Leakage Protection Prevents Battery Drainage
  • ±0.5% Voltage Regulation Accuracy
  • Thermal Regulation Maximizes Charge Rate
  • Charge Termination by Minimum Current and Time
  • Precharge Conditioning With Safety Timer
  • Status Outputs for LED or System Interface Indicate Charge, Fault, and Power Good Outputs
  • Short-Circuit and Thermal Protection
  • Automatic Sleep Mode for Low Power Consumption
  • Small 3×3 mm MLP Package
  • Selectable Battery Insertion and Battery Absent Detection
  • Input Overvoltage Protection
    • 6.5 V and 10.5 V Options

2 Applications

  • PDA, MP3 Players, Digital Cameras
  • Internet Appliances and Handheld Devices

3 Description

The bq2408x series are highly integrated Li-Ion and Li-Pol linear chargers, targeted at space-limited portable applications. The bq2408x series offers a variety of protection features and functional options, while still implementing a complete charging system in a small package. The battery is charged in three phases: conditioning, constant or thermally regulated current, and constant voltage. Charge is terminated based on minimum current. An internal programmable charge timer provides a backup protection feature for charge termination and is dynamically adjusted during the thermal regulation phase. The bq2408x automatically restarts the charge if the battery voltage falls below an internal threshold; sleep mode is set when the external input supply is removed. Multiple versions of this device family enable easy design of the bq2408x in cradle chargers or in the end equipment, while using low cost or high-end AC adapters.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
bq2408x VSON (10) 3.00 mm × 3.00 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Typical Application Circuit

bq24085 bq24086 bq24087 bq24088 typ_app_lus784.gif