SLUSEG4B December   2022  – February 2024 BQ25628 , BQ25629

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Description (continued)
  6. 5 Device Comparison
  7. 6 Pin Configuration and Functions
  8. 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 Typical Characteristics
  9. 8 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 D+/D– Detection Sets Input Current Limit (BQ25629)
        4. 8.3.3.4 ILIM Pin (BQ25628 Only)
        5. 8.3.3.5 Input Voltage Limit Threshold Setting (VINDPM Threshold)
        6. 8.3.3.6 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 Cold/Hot Temperature Window in OTG Mode
          4. 8.3.5.4.4 JEITA Charge Rate Scaling
          5. 8.3.5.4.5 TS_BIAS Pin
        5. 8.3.5.5 Charging Safety Timers
      6. 8.3.6  USB On-The-Go (OTG)
        1. 8.3.6.1 Boost OTG Mode
        2. 8.3.6.2 Bypass OTG Mode
        3. 8.3.6.3 PMID Voltage Indicator (PMID_GD)
      7. 8.3.7  Integrated 12-Bit ADC for Monitoring
      8. 8.3.8  Status Outputs ( STAT, INT)
        1. 8.3.8.1 Interrupts and Status, Flag and Mask Bits
        2. 8.3.8.2 Charging Status Indicator (STAT)
        3. 8.3.8.3 Interrupt to Host ( INT)
      9. 8.3.9  BATFET Control
        1. 8.3.9.1 Shutdown Mode
        2. 8.3.9.2 Ship Mode
        3. 8.3.9.3 System Power Reset
      10. 8.3.10 Protections
        1. 8.3.10.1 Voltage and Current Monitoring in Battery Only and HIZ Modes
          1. 8.3.10.1.1 Battery Undervoltage Lockout
          2. 8.3.10.1.2 Battery Overcurrent Protection
        2. 8.3.10.2 Voltage and Current Monitoring in Buck Mode
          1. 8.3.10.2.1 Input Overvoltage
          2. 8.3.10.2.2 System Overvoltage Protection (SYSOVP)
          3. 8.3.10.2.3 Forward Converter Cycle-by-Cycle Current Limit
          4. 8.3.10.2.4 System Short
          5. 8.3.10.2.5 Battery Overvoltage Protection (BATOVP)
          6. 8.3.10.2.6 Sleep and Poor Source Comparators
          7. 8.3.10.2.7 PMID OVP and VBUS Overcurrent
        3. 8.3.10.3 Voltage and Current Monitoring in Boost Mode
          1. 8.3.10.3.1 Boost Mode Overvoltage Protection
          2. 8.3.10.3.2 Boost Mode Duty Cycle Protection
          3. 8.3.10.3.3 Boost Mode PMID Undervoltage Protection
          4. 8.3.10.3.4 Boost Mode Battery Undervoltage
          5. 8.3.10.3.5 Boost Converter Cycle-by-Cycle Current Limit
          6. 8.3.10.3.6 Boost Mode SYS Short
        4. 8.3.10.4 Voltage and Current Monitoring in Bypass Mode
          1. 8.3.10.4.1 Bypass Mode Overvoltage Protection
          2. 8.3.10.4.2 Bypass Mode Battery OCP
          3. 8.3.10.4.3 Bypass Mode Reverse-Current Protection
          4. 8.3.10.4.4 Bypass Mode Battery Undervoltage
          5. 8.3.10.4.5 Bypass Mode SYS Short
          6. 8.3.10.4.6 Bypass Mode REGN Fault
        5. 8.3.10.5 Thermal Regulation and Thermal Shutdown
          1. 8.3.10.5.1 Thermal Protection in Buck Mode
          2. 8.3.10.5.2 Thermal Protection in Boost Mode
          3. 8.3.10.5.3 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 BQ25628 Registers
  10. 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
      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

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • RYK|18
Thermal pad, mechanical data (Package|Pins)
Orderable Information

4 Description (continued)

The BQ25628 has the ILIM pin to set the default input current limit and TS_BIAS pin for controlled thermistor bias. The BQ25629 supports a wide range of input sources, including standard USB host port and USB charging port. The device is compliant with USB 2.0 and USB 3.0 power specifications for input current and voltage regulation and meets the USB On-the-Go (OTG) operation power rating specification up to 2.0A.

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 BQ25628 and BQ25629 power an accessory attached to PMID either directly from the adapter or from the battery in either boost or bypass OTG modes. Boost OTG provides a regulated voltage at PMID from the battery via boost operation in the converter. Bypass OTG provides a direct path from the battery to PMID for highest efficiency. The BQ25628 and BQ25629 may be configured to automatically transition into boost OTG mode when the adapter is removed, and back into forward charging when the adapter is attached in order to power PMID in either configuration without host intervention. In forward charging, boost OTG and bypass OTG, the PMID_GD signal indicates PMID voltage and current are within accepted ranges. PMID_GD may be used to drive an external PMOS FET to protect attached accessories by disconnecting them from PMID if an out-of-range voltage or current is detected.

The BQ25628 and BQ25629 initiate 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 BQ25628 and BQ25629 provide 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 and OTG boost mode, thermal shutdown and input UVLO and overvoltage protection. The INT output notifies the host when a fault occurs or status changes.

The BQ25628 and BQ25629 are available in a 18-pin, 2.5mm × 3.0mm WQFN package.