SLUSF60 December   2023 BQ77307

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Recommended Operating Conditions
    4. 6.4  Thermal Information BQ77307
    5. 6.5  Supply Current
    6. 6.6  Digital I/O
    7. 6.7  REGOUT LDO
    8. 6.8  Voltage References
    9. 6.9  Current Detector
    10. 6.10 Thermistor Pullup Resistor
    11. 6.11 Hardware Overtemperature Detector
    12. 6.12 Internal Oscillator
    13. 6.13 Charge and Discharge FET Drivers
    14. 6.14 Protection Subsystem
    15. 6.15 Timing Requirements - I2C Interface, 100kHz Mode
    16. 6.16 Timing Requirements - I2C Interface, 400kHz Mode
    17. 6.17 Timing Diagram
    18. 6.18 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Device Configuration
      1. 7.3.1 Commands and Subcommands
      2. 7.3.2 Configuration Using OTP or Registers
      3. 7.3.3 Device Security
    4. 7.4 Device Hardware Features
      1. 7.4.1  Voltage Protection Subsystem
      2. 7.4.2  Current Protection Subsystem
      3. 7.4.3  Unused VC Pins
      4. 7.4.4  Internal Temperature Protection
      5. 7.4.5  Thermistor Temperature Protections
      6. 7.4.6  Protection FET Drivers
      7. 7.4.7  Voltage References
      8. 7.4.8  Multiplexer
      9. 7.4.9  LDOs
      10. 7.4.10 Standalone Versus Host Interface
      11. 7.4.11 ALERT Pin Operation
      12. 7.4.12 Low Frequency Oscillator
      13. 7.4.13 I2C Serial Communications Interface
    5. 7.5 Protection Subsystem
      1. 7.5.1 Protections Overview
      2. 7.5.2 Primary Protections
      3. 7.5.3 Cell Open Wire Protection
      4. 7.5.4 Diagnostic Checks
    6. 7.6 Device Power Modes
      1. 7.6.1 Overview of Power Modes
      2. 7.6.2 NORMAL Mode
      3. 7.6.3 SHUTDOWN Mode
      4. 7.6.4 CONFIG_UPDATE Mode
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Performance Plot
      4. 8.2.4 Random Cell Connection Support
      5. 8.2.5 Startup Timing
      6. 8.2.6 FET Driver Turn-Off
      7. 8.2.7 Usage of Unused Pins
  10. 9 Power Supply Recommendations
  11. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  12. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  13. 12Revision History
  14. 13Mechanical, Packaging, and Orderable Information

Package Options

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

9 Power Supply Recommendations

The BQ77307 device draws its supply current from the BAT pin, which is typically connected to the top of stack point through a series diode, to protect against any fault within the device resulting in unintended charging of the pack. A series resistor and capacitor is included to lowpass filter fast variations on the stack voltage. During a short circuit event, the stack voltage may be momentarily pulled to a very low voltage before the protection FETs are disabled. In this case, the charge on the BAT pin capacitor will temporarily support the BQ77307 device's supply current, to avoid the device losing power.

The REGSRC pin serves as the supply voltage for the integrated REGOUT customer regulator and for the CHG and DSG FET drivers. This pin can also be connected to the top of stack through a diode, to similarly allow the voltage to hold up longer during a short circuit event. If a diode or any series resistance (> 1 Ω) is included between the top of stack and the REGSRC pin, a minimum 1-μF capacitor is recommended to be included at the REGSRC pin to VSS. It is also acceptable to short the REGSRC pin to the BAT pin, such that the same diode and filter circuit can support both pins. However, the load on the REGOUT pin will discharge the BAT capacitor faster in this case and should be considered by the system designer.