SLUSEC9A October   2020  – March 2021 BQ25618E , BQ25619E

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Device Comparison Table
  7. 7 Pin Configuration and Functions
  8. 8 Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 Timing Requirements
    7. 8.7 Typical Characteristics
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Power-On-Reset (POR)
      2. 9.3.2 Device Power Up From Battery Without Input Source
      3. 9.3.3 Power Up From Input Source
        1. 9.3.3.1 Power Up REGN LDO
        2. 9.3.3.2 Poor Source Qualification
        3. 9.3.3.3 Input Source Type Detection (IINDPM Threshold)
          1. 9.3.3.3.1 PSEL Pins Sets Input Current Limit
        4. 9.3.3.4 Input Voltage Limit Threshold Setting (VINDPM Threshold)
        5. 9.3.3.5 Power Up Converter in Buck Mode
        6. 9.3.3.6 HIZ Mode with Adapter Present
      4. 9.3.4 Power Path Management
        1. 9.3.4.1 Narrow Voltage DC (NVDC) Architecture
        2. 9.3.4.2 Dynamic Power Management
        3. 9.3.4.3 Supplement Mode
      5. 9.3.5 Battery Charging Management
        1. 9.3.5.1 Autonomous Charging Cycle
        2. 9.3.5.2 Battery Charging Profile
        3. 9.3.5.3 Charging Termination
        4. 9.3.5.4 Thermistor Qualification
          1. 9.3.5.4.1 JEITA Guideline Compliance During Charging Mode
        5. 9.3.5.5 Charging Safety Timer
      6. 9.3.6 Ship Mode and QON Pin
        1. 9.3.6.1 BATFET Disable (Enter Ship Mode)
        2. 9.3.6.2 BATFET Enable (Exit Ship Mode)
        3. 9.3.6.3 BATFET Full System Reset
      7. 9.3.7 Status Outputs ( STAT, INT , PG )
        1. 9.3.7.1 Power Good Indicator (PG_STAT Bit; BQ25619E only)
        2. 9.3.7.2 Charging Status Indicator (STAT)
        3. 9.3.7.3 Interrupt to Host ( INT)
      8. 9.3.8 Protections
        1. 9.3.8.1 Voltage and Current Monitoring in Buck Mode
          1. 9.3.8.1.1 Input Overvoltage Protection (ACOV)
          2. 9.3.8.1.2 System Overvoltage Protection (SYSOVP)
        2. 9.3.8.2 Thermal Regulation and Thermal Shutdown
          1. 9.3.8.2.1 Thermal Protection in Buck Mode
        3. 9.3.8.3 Battery Protection
          1. 9.3.8.3.1 Battery Overvoltage Protection (BATOVP)
          2. 9.3.8.3.2 Battery Overdischarge Protection
          3. 9.3.8.3.3 System Overcurrent Protection
      9. 9.3.9 Serial Interface
        1. 9.3.9.1 Data Validity
        2. 9.3.9.2 START and STOP Conditions
        3. 9.3.9.3 Byte Format
        4. 9.3.9.4 Acknowledge (ACK) and Not Acknowledge (NACK)
        5. 9.3.9.5 Slave Address and Data Direction Bit
        6. 9.3.9.6 Single Read and Write
        7. 9.3.9.7 Multi-Read and Multi-Write
    4. 9.4 Device Functional Modes
      1. 9.4.1 Host Mode and Default Mode
    5. 9.5 Register Maps
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Inductor Selection
        2. 10.2.2.2 Input Capacitor and Resistor
        3. 10.2.2.3 Output Capacitor
      3. 10.2.3 Application Curves
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Device Support
      1. 13.1.1 Third-Party Products Disclaimer
    2. 13.2 Documentation Support
      1. 13.2.1 Related Documentation
    3. 13.3 Receiving Notification of Documentation Updates
    4. 13.4 Support Resources
    5. 13.5 Trademarks
    6. 13.6 Electrostatic Discharge Caution
    7. 13.7 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

10.2.2.1 Inductor Selection

The 1.5-MHz switching frequency allows the use of small inductor and capacitor values to maintain an inductor saturation current higher than the charging current (ICHG) plus half the ripple current (IRIPPLE):

Equation 3. ISAT ≥ ICHG + (1/2) IRIPPLE

The inductor ripple current depends on the input voltage (VVBUS), the duty cycle (D = VBAT/VVBUS), the switching frequency (fS) and the inductance (L).

Equation 4. GUID-AD290143-CD31-41D9-AED0-E907E104325B-low.gif

The maximum inductor ripple current occurs when the duty cycle (D) is 0.5 or approximately 0.5. Usually inductor ripple is designed in the range between 20% and 40% maximum charging current as a trade-off between inductor size and efficiency for a practical design.