SLUSB76B February   2013  – May 2015

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Pin Configuration and Functions
  7. 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 Typical Performance Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagrams
    3. 8.3 Feature Description
      1. 8.3.1  Input Voltage Protection
        1. 8.3.1.1 Input Overvoltage Protection
        2. 8.3.1.2 Bad Adaptor Detection/Rejection
        3. 8.3.1.3 Sleep Mode
        4. 8.3.1.4 Input Voltage Based DPM (Special Charger Voltage Threshold)
      2. 8.3.2  Battery Protection
        1. 8.3.2.1 Output Overvoltage Protection
        2. 8.3.2.2 Battery Short Protection
        3. 8.3.2.3 Battery Detection in HOST Mode
      3. 8.3.3  DEFAULT Mode
      4. 8.3.4  USB Friendly Power Up
      5. 8.3.5  Input Current Limiting at Power Up
      6. 8.3.6  Factory Mode
      7. 8.3.7  Spread Spectrum Mode
      8. 8.3.8  PWM Controller in Charge Mode
      9. 8.3.9  Battery Charging Process
      10. 8.3.10 Thermal Regulation and Protection
      11. 8.3.11 Charge Status Output, STAT Pin
      12. 8.3.12 Control Bits in Charge Mode
        1. 8.3.12.1 CE Bit (Charge Mode)
        2. 8.3.12.2 RESET Bit
        3. 8.3.12.3 OPA_MODE Bit
      13. 8.3.13 Control Pins in Charge Mode
        1. 8.3.13.1 CD Pin (Charge Disable)
      14. 8.3.14 Boost Mode Operation
        1. 8.3.14.1 PWM Controller in Boost Mode
        2. 8.3.14.2 Boost Start Up
        3. 8.3.14.3 PFM Mode at Light Load
        4. 8.3.14.4 Protection in Boost Mode
          1. 8.3.14.4.1 Output Overvoltage Protection
          2. 8.3.14.4.2 Output Overload Protection
          3. 8.3.14.4.3 Battery Overvoltage Protection
        5. 8.3.14.5 STAT Pin in Boost Mode
      15. 8.3.15 High Impedance (Hi-Z) Mode
      16. 8.3.16 Serial Interface Description
        1. 8.3.16.1 F/S Mode Protocol
        2. 8.3.16.2 HS Mode Protocol
        3. 8.3.16.3 I2C Update Sequence
        4. 8.3.16.4 Slave Address Byte
        5. 8.3.16.5 Register Address Byte
    4. 8.4 Device Functional Modes
      1. 8.4.1 Charge Mode Operation
        1. 8.4.1.1 Charge Profile
    5. 8.5 Register Maps
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Charge Current Sensing Resistor Selection Guidelines
        2. 9.2.2.2 Output Inductor and Capacitance Selection Guidelines
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
    1. 10.1 System Load After Sensing Resistor
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information
    1. 13.1 Package Summary
      1. 13.1.1 Chip Scale Packaging Dimensions

Package Options

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

1 Features

  • Integrated Power FETs for up to 1.55-A Charge Rate
  • Spread Spectrum Frequency Control for Improved EMI Performance
  • High-Accuracy Voltage and Current Regulation
    • Input Current Regulation Accuracy:
      ±5% (100 mA and 500 mA)
    • Charge Voltage Regulation Accuracy:
      ±0.5% (25°C), ±1% (0°C to 125°C)
    • Charge Current Regulation Accuracy: ±5%
  • Factory Test-Mode for GSM Calibration Without a Battery
  • Input Voltage Based Dynamic Power Management (VIN DPM)
  • Bad Adaptor Detection and Rejection
  • Safety Limit Register for Maximum Charge Voltage and Current Limiting
  • High-Efficiency Mini-USB/AC Battery Charger for Single-Cell Li-Ion and Li-Polymer Battery Packs
  • 20-V Absolute Maximum Input Voltage Rating
  • 6.5-V Maximum Operating Input Voltage
  • Programmable Charge Parameters through I2C Compatible Interface (up to 3.4 Mbps):
    • Input Current Limit
    • VIN DPM Threshold
    • Fast-Charge/Termination Current
    • Charge Regulation Voltage (3.5 to 4.44 V)
    • Low Charge Current Mode Enable/Disable
    • Termination Enable/Disable
  • Synchronous Fixed-Frequency PWM Controller Operating at 3 MHz With 0% to 99.5% Duty Cycle
  • Automatic High Impedance Mode for Low Power Consumption
  • Robust Protection
    • Reverse Leakage Protection Prevents Battery Drainage
    • Thermal Regulation and Protection
    • Input/Output Overvoltage Protection
  • Status Output for Charging and Faults
  • USB Friendly Boot-Up Sequence
  • Automatic Charging
  • Power Up System Without Battery
  • Boost Mode Operation for USB OTG:
    • Input Voltage Range (from Battery):
      3.2 to 4.5 V
    • Output for VBUS: 5.05 V, 350 mA
  • 2.1 × 2.0-mm, 20-Pin DSBGA Package
  • Pin-to-Pin Compatible With bq24157 and bq24158

2 Applications

  • Mobile and Smart Phones
  • MP3 Players
  • Handheld Devices

3 Description

The bq24157S is a compact, flexible, high-efficiency, USB-friendly switch-mode charge management device for single-cell Li-ion and Li-polymer batteries used in a wide range of portable applications. The charge parameters can be programmed through an I2C interface. The IC integrates a synchronous PWM controller, power MOSFETs, input current sensing, high-accuracy current and voltage regulation, and charge termination, into a small DSBGA package.

The IC charges the battery in three phases: conditioning, constant current, and constant voltage. The input current is automatically limited to the value set by the host.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
bq24157S DSBGA (20) 2.10 mm × 2.00 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Typical Application Circuit

bq24157S fp_app_circuit_lusb76.gif
A. Use RSNS = 68 mΩ to program up to 1.25-A charge current, use RSNS = 55 mΩ to program up to 1.55-A charge current. For detailed instructions, refer to the Detailed Design Procedure.

4 Revision History

Changes from A Revision (June 2014) to B Revision

Changes from * Revision (February 2013) to A Revision

  • Added the Handling Ratings table, Detailed Description section, Feature Description section, Device Functional Modes section, Register Maps section, Application and Implementation section. Power Supply Recommendations section, Layout section, Device and Documentation Support section, Mechanical, Packaging, and Orderable Information sectionGo