SLUSA55B October   2010  – April 2015

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Device Comparison Table
  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 Typical Characteristics
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Battery Voltage Regulation
      2. 8.3.2  Battery Current Regulation
      3. 8.3.3  Input Adapter Current Regulation
      4. 8.3.4  Precharge
      5. 8.3.5  Charge Termination, Recharge, and Safety Timer
      6. 8.3.6  Power Up
      7. 8.3.7  Enable and Disable Charging
      8. 8.3.8  System Power Selector
      9. 8.3.9  Automatic Internal Soft-Start Charger Current
      10. 8.3.10 Converter Operation
      11. 8.3.11 Synchronous and Nonsynchronous Operation
      12. 8.3.12 Cycle-by-Cycle Charge Undercurrent Protection
      13. 8.3.13 Input Overvoltage Protection (ACOV)
      14. 8.3.14 Input Undervoltage Lockout (UVLO)
      15. 8.3.15 Battery Overvoltage Protection
      16. 8.3.16 Cycle-by-Cycle Charge Overcurrent Protection
      17. 8.3.17 Thermal Shutdown Protection
      18. 8.3.18 Temperature Qualification
      19. 8.3.19 Timer Fault Recovery
      20. 8.3.20 PG Output
      21. 8.3.21 CE (Charge Enable)
      22. 8.3.22 Charge Status Outputs
      23. 8.3.23 Battery Detection
    4. 8.4 Device Functional Modes
  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 Inductor Selection
        2. 9.2.2.2 Input Capacitor
        3. 9.2.2.3 Output Capacitor
        4. 9.2.2.4 Power MOSFET Selection
        5. 9.2.2.5 Input Filter Design
        6. 9.2.2.6 Inductor, Capacitor, and Sense Resistor Selection Guidelines
        7. 9.2.2.7 Component List for Typical System Circuit of
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  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

Package Options

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

1 Features

  • USB-Friendly 4.7-V to 28-V Input Operating Range
  • Stand-Alone Charge Controller to Support 1 to 6 Li-Ion or Li-Polymer Battery Cells
  • Up to 10-A Charge Current and Adapter Current
  • 600-kHz NMOS-NMOS Synchronous Buck Converter
  • High-Accuracy Voltage and Current Regulation
    • ±0.5% Charge Voltage Accuracy
    • ±3% Charge Current Accuracy
    • ±3% Adapter Current Accuracy
  • Integration
    • Automatic System Power Selection From Adapter or Battery
    • Internal Loop Compensation
    • Internal Soft Start
    • Dynamic Power Management
  • Safety Protection
    • Input Overvoltage Protection
    • Battery Thermistor Sense Hot/Cold Charge Suspend
    • Battery Detection
    • Reverse-Protection Input FET
    • Programmable Safety Timer
    • Charge Overcurrent Protection
    • Battery Short Protection
    • Battery Overvoltage Protection
    • Thermal Shutdown
  • Status Outputs
    • Adapter Present
    • Charger Operation Status
  • Charge Enable Pin
  • 6-V Gate Drive for Synchronous Buck Converter
  • 30-ns Driver Dead-Time and 99.5% Maximum Effective Duty Cycle
  • Energy Star Low Quiescent Current Iq
    • < 15-µA Off-State Battery Discharge Current
    • < 1.5-mA Off-State Input Quiescent Current

2 Applications

  • Tablet PCs
  • Smart Phones
  • Portable Media Players, Navigation Devices, Notebooks and Ultra-Mobile PCs
  • Personal Digital Assistants
  • Handheld Terminals
  • Industrial and Medical Equipment

3 Description

The bq24618 device is highly integrated Li-ion or Li-polymer switched-mode battery-charge controller. The bq24618 offers a constant-frequency synchronous switching PWM controller with high-accuracy charge current and voltage regulation, charge preconditioning, termination, adapter current regulation and charge status monitoring.

The bq24618 operates from either a USB port or AC adapter and supports charge currents up to 10 A. The device charges the battery in three phases: preconditioning, constant current, and constant voltage. Charge is terminated when the current reaches a minimum user-selectable level. A programmable charge timer provides a safety backup for charge termination. The bq24618 automatically restarts the charge cycle if the battery voltage falls below an internal threshold, and enters a low-quiescent current sleep mode when the input voltage falls below the battery voltage.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
bq24618 VQFN (24) 4.00 mm × 4.00 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Simplified Schematic

bq24618 Simplified schematic.gif

4 Revision History

Changes from A Revision (October 2011) to B Revision

  • Added ESD Ratings table, Feature Description section, Device Functional Modes, Application and Implementation section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and Mechanical, Packaging, and Orderable Information section. Go

Changes from * Revision (October 2010) to A Revision