SLUSFA4B June   2023  – February 2024 BQ25628E

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Description (continued)
  6. Device Comparison
  7. Pin Configuration and Functions
  8. 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 Typical Characteristics
  9. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Power-On-Reset (POR)
      2. 8.3.2 Device Power Up from Battery
      3. 8.3.3 Device Power Up from Input Source
        1. 8.3.3.1 REGN LDO Power Up
        2. 8.3.3.2 Poor Source Qualification
        3. 8.3.3.3 ILIM Pin
        4. 8.3.3.4 Input Voltage Limit Threshold Setting (VINDPM Threshold)
        5. 8.3.3.5 Converter Power-Up
      4. 8.3.4 Power Path Management
        1. 8.3.4.1 Narrow VDC Architecture
        2. 8.3.4.2 Dynamic Power Management
        3. 8.3.4.3 High Impedance Mode
      5. 8.3.5 Battery Charging Management
        1. 8.3.5.1 Autonomous Charging Cycle
        2. 8.3.5.2 Battery Charging Profile
        3. 8.3.5.3 Charging Termination
        4. 8.3.5.4 Thermistor Qualification
          1. 8.3.5.4.1 Advanced Temperature Profile in Charge Mode
          2. 8.3.5.4.2 TS Pin Thermistor Configuration
          3. 8.3.5.4.3 JEITA Charge Rate Scaling
          4. 8.3.5.4.4 TS_BIAS Pin
        5. 8.3.5.5 Charging Safety Timers
      6. 8.3.6 Integrated 12-Bit ADC for Monitoring
      7. 8.3.7 Status Outputs ( PG, STAT, INT)
        1. 8.3.7.1 PG Pin Power Good Indicator
        2. 8.3.7.2 Interrupts and Status, Flag and Mask Bits
        3. 8.3.7.3 Charging Status Indicator (STAT)
        4. 8.3.7.4 Interrupt to Host ( INT)
      8. 8.3.8 BATFET Control
        1. 8.3.8.1 Shutdown Mode
        2. 8.3.8.2 Ship Mode
        3. 8.3.8.3 System Power Reset
      9. 8.3.9 Protections
        1. 8.3.9.1 Voltage and Current Monitoring in Battery Only and HIZ Modes
          1. 8.3.9.1.1 Battery Undervoltage Lockout
          2. 8.3.9.1.2 Battery Overcurrent Protection
        2. 8.3.9.2 Voltage and Current Monitoring in Buck Mode
          1. 8.3.9.2.1 Input Overvoltage
          2. 8.3.9.2.2 System Overvoltage Protection (SYSOVP)
          3. 8.3.9.2.3 Forward Converter Cycle-by-Cycle Current Limit
          4. 8.3.9.2.4 System Short
          5. 8.3.9.2.5 Battery Overvoltage Protection (BATOVP)
          6. 8.3.9.2.6 Sleep and Poor Source Comparators
        3. 8.3.9.3 Thermal Regulation and Thermal Shutdown
          1. 8.3.9.3.1 Thermal Protection in Buck Mode
          2. 8.3.9.3.2 Thermal Protection in Battery-Only Mode
    4. 8.4 Device Functional Modes
      1. 8.4.1 Host Mode and Default Mode
      2. 8.4.2 Register Bit Reset
    5. 8.5 Programming
      1. 8.5.1 Serial Interface
        1. 8.5.1.1 Data Validity
        2. 8.5.1.2 START and STOP Conditions
        3. 8.5.1.3 Byte Format
        4. 8.5.1.4 Acknowledge (ACK) and Not Acknowledge (NACK)
        5. 8.5.1.5 Target Address and Data Direction Bit
        6. 8.5.1.6 Single Write and Read
        7. 8.5.1.7 Multi-Write and Multi-Read
    6. 8.6 Register Maps
      1. 8.6.1 Register Programming
      2. 8.6.2 BQ25628E Registers
  10. 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
      3. 9.2.3 Application Curves
  11. 10Power Supply Recommendations
  12. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  13. 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 Receiving Notification of Documentation Updates
    4. 12.4 Support Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  14. 13Revision History
  15. 14Mechanical, Packaging, and Orderable Information

Package Options

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

Description (continued)

The BQ25628E has an ILIM pin to set the default input current limit and TS_BIAS pin for controlled thermistor bias.

The power path management regulates the system slightly above battery voltage but does not drop below the programmable minimum system voltage. With this feature, the system maintains operation even when the battery is completely depleted or removed. When the input current limit or input voltage limit is reached, the power path management automatically reduces the charge current. As the system load continues to increase, the battery starts to discharge until the system power requirement is met. This supplement mode prevents overloading the input source.

The BQ25628E initiates and complete a charging cycle without host control. By sensing the battery voltage, it charges the battery in four different phases: trickle charge, pre-charge, constant current (CC) charge and constant voltage (CV) charge. At the end of the charging cycle, the charger automatically terminates when the charge current is below a preset threshold and the battery voltage is higher than the recharge threshold. Termination is supported for all TS pin temperature zones.

The BQ25628E provides various safety features for battery charging and system operations, including battery negative temperature coefficient thermistor monitoring, charging safety timer and overvoltage and overcurrent protections. The thermal regulation reduces charge current when the junction temperature exceeds the programmable threshold. The STAT output reports the charging status and any fault conditions. Other safety features include battery temperature sensing for charge mode, thermal shutdown and input UVLO and overvoltage protection. The INT output notifies the host when a fault occurs or status changes.

The BQ25628E is available in a 18-pin, 2.5mm × 3.0mm WQFN package.