SLUSEG2C September   2022  – February 2024 BQ25620 , BQ25622

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 (BQ25620 Only)
        4. 8.3.3.4 ILIM Pin (BQ25622 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 (BQ25622 Only)
        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
      7. 8.3.7  Integrated 12-Bit ADC for Monitoring
      8. 8.3.8  Status Outputs ( PG, STAT, INT)
        1. 8.3.8.1 PG Pin Power Good Indicator
        2. 8.3.8.2 Interrupts and Status, Flag and Mask Bits
        3. 8.3.8.3 Charging Status Indicator (STAT)
        4. 8.3.8.4 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
        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 Thermal Regulation and Thermal Shutdown
          1. 8.3.10.4.1 Thermal Protection in Buck Mode
          2. 8.3.10.4.2 Thermal Protection in Boost Mode
          3. 8.3.10.4.3 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 BQ25620 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

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

8.3.3.6 Converter Power-Up

After the input current and voltage limits are set, the converter is enabled and the HSFET and LSFET start switching. If battery charging is disabled, the BATFET turns off. Otherwise, the BATFET stays on to charge the battery. Converter startup requires the following conditions:

  • VBUS has passed poor source qualification (refer to Section 8.3.3.2)
  • VBUS > VBAT + VSLEEPZ
  • VVBUS < VVBUS_OVP
  • EN_HIZ = 0
  • VSYS < VSYS_OVP
  • TJ < TSHUT

The BQ25620 and BQ25622 provide soft start when the system rail is ramped up by setting IINDPM to its lowest programmable value and stepping up through each available setting until reaching the value set by IINDPM register. Concurrently, the system short protection limits the output current to approximately 0.5 A when the system rail is below VSYS_SHORT.

The device uses a highly efficient 1.5-MHz, fixed frequency pulse width modulated (PWM) step-down switching regulator. The internally compensated feedback loop keep tight control of the switching frequency under all conditions of input voltage, battery voltage, charge current and temperature, simplifying output filter design.

The device switches to pulse frequency modulation (PFM) control at light load condition. The PFM_FWD_DIS and PFM_OTG_DIS bits can be used to disable the PFM operation in buck and boost respectively.