SLUSCU0L march   2018  – august 2023 BQ77915

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Description (continued)
  7. 6 Device Comparison Table
  8. 7 Pin Configuration and Functions
  9. 8 Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 Typical Characteristics
  10. 9 Detailed Description
    1. 9.1 Overview
      1. 9.1.1 Device Functionality Summary
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  Protection Summary
      2. 9.3.2  Fault Operation
        1. 9.3.2.1  Operation in OV
        2. 9.3.2.2  Operation in UV
        3. 9.3.2.3  Operation in OW
        4. 9.3.2.4  Operation in OCD1
        5. 9.3.2.5  Operation in OCD2
        6. 9.3.2.6  Programming the OCD1/2 Delay Using the OCDP Pin
        7. 9.3.2.7  Operation in SCD
        8. 9.3.2.8  Operation in OCC
        9. 9.3.2.9  Overcurrent Recovery Timer
        10. 9.3.2.10 Load Detection and Load Removal Detection
        11. 9.3.2.11 Operation in OTC
        12. 9.3.2.12 Operation in OTD
        13. 9.3.2.13 Operation in UTC
        14. 9.3.2.14 Operation in UTD
      3. 9.3.3  Protection Response and Recovery Summary
      4. 9.3.4  Cell Balancing
      5. 9.3.5  HIBERNATE Mode Operation
      6. 9.3.6  Configuration CRC Check and Comparator Built-In-Self-Test
      7. 9.3.7  Fault Detection Method
        1. 9.3.7.1 Filtered Fault Detection
      8. 9.3.8  State Comparator
      9. 9.3.9  DSG FET Driver Operation
      10. 9.3.10 CHG FET Driver Operation
      11. 9.3.11 External Override of CHG and DSG Drivers
      12. 9.3.12 Configuring 3-Series, 4-Series, or 5-Series Modes
      13. 9.3.13 Stacking Implementations
      14. 9.3.14 Zero-Volt Battery Charging Inhibition
    4. 9.4 Device Functional Modes
      1. 9.4.1 Power Modes
        1. 9.4.1.1 Power On Reset (POR)
        2. 9.4.1.2 NORMAL Mode
        3. 9.4.1.3 FAULT Mode
        4. 9.4.1.4 HIBERNATE Mode
        5. 9.4.1.5 SHUTDOWN Mode
        6. 9.4.1.6 Customer Fast Production Test Modes
  11. 10Application and Implementation
    1. 10.1 Application Information
      1. 10.1.1 Recommended System Implementation
        1. 10.1.1.1 CHG and DSG FET Rise and Fall Time
        2. 10.1.1.2 Protecting CHG and LD
        3. 10.1.1.3 Protecting the CHG FET
        4. 10.1.1.4 Using Load Detect for UV Fault Recovery
        5. 10.1.1.5 Temperature Protection
        6. 10.1.1.6 Adding RC Filters to the Sense Resistor
        7. 10.1.1.7 Using the State Comparator in an Application
          1. 10.1.1.7.1 Examples
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Design Example
      3. 10.2.3 Application Curves
  12. 11Power Supply Recommendations
  13. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  14. 13Device and Documentation Support
    1. 13.1 Third-Party Products Disclaimer
    2. 13.2 Documentation Support
      1. 13.2.1 Related Documentation
    3. 13.3 Receiving Notification of Documentation Updates
    4. 13.4 Support Resources
    5. 13.5 Trademarks
    6. 13.6 Electrostatic Discharge Caution
    7. 13.7 Glossary
  15. 14Mechanical, Packaging, and Orderable Information

Package Options

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

10.1.1.4 Using Load Detect for UV Fault Recovery

A larger CHG FET gate-source resistor is required if load removal is enabled as a device of the UV recovery criteria. When the load removal circuit is enabled, the device is internally connected to VSS. Because in a UV fault, the CHG driver remains on, it creates a resistor divider path to the load detect circuit.

GUID-634FAE4C-3385-474D-BF98-0F92183D2935-low.svgFigure 10-6 Load Detect Circuit During UV Fault

To verify load removal is detected properly during a UV fault, use 3.3 MΩ for RGS_CHG (instead of a typical 1 MΩ when load removal is not required for UV recovery). RCHG can stay in 1 MΩ as recommended when using CHG FET protection components. The CHG FET rise time impact is minimized, as described in Protecting the CHG FET. On a stacked configuration, connect the LD pin as shown in Figure 10-7 if load removal is used for a UV fault recovery. If load detection is not required for a UV fault recovery, a larger value of RGS_CHG can be used (that is, 10 MΩ), and the LD pin on the upper devices can be left floating.

GUID-7C46F089-84B3-4014-82BD-60C455F5A1FD-low.svgFigure 10-7 Simplified Circuit: LD Connection on Upper Device When Using for UV Fault Recovery