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

8.3.6.2 Bypass OTG Mode

In addition to boost OTG mode, the BQ25628 and BQ25629 provide bypass mode to directly connect the battery to PMID pin through BATFET and HSFET. The low impedance path in bypass mode achieves the highest efficiency when powering up external accessories, and maximizes the battery run time. During bypass OTG mode, the status register VBUS_STAT is set to 111.

Bypass OTG mode is entered when:

  • VBAT > VBAT_OTG
  • VVBUS < VBAT+VSLEEP
  • OTG mode has been enabled (EN_OTG=1) and bypass mode is enabled (EN_BYPASS_OTG=1).
  • VTS_OTG_HOT < VTS < VTS_OTG_COLD
  • VREGN > VREGN_OK
  • 30 ms delay after EN_OTG = EN_BYPASS_OTG = 1, bypass OTG is enabled by turning on HSFET and BATFET.

Any of the following conditions will exit from bypass OTG. Unless otherwise indicated, exit from bypass mode leads into battery-only mode by setting EN_OTG = EN_BYPASS_OTG = 0:

  • OTG mode is disabled (EN_OTG=0)
  • Bypass OTG mode is disabled (EN_BYPASS_OTG = 0) will cause exit into boost OTG mode if EN_OTG remains at 1.
  • Entry into shutdown, ship mode or system power reset will exit from bypass OTG by setting EN_OTG = EN_BYPASS_OTG = 0 and then enter into shutdown, ship mode or system power reset as selected.

BQ25628 and BQ25629 can be configured to automatically transition between charging mode and bypass OTG mode by setting EN_CHG = 1, EN_OTG = 1 and EN_BYPASS_OTG = 1. When the adapter plugs in, and all conditions to start a new charge cycle are valid, the device automatically transitions to charging mode. If the adapter is removed and bypass enable conditions are valid, the device automatically transitions to bypass OTG mode to power the accessories connected to PMID.