ZHCSHD3L October   2017  – March 2025 BQ2980 , BQ2982

PRODUCTION DATA  

  1.   1
  2. 1 特性
  3. 2 应用
  4. 3 说明
  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
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
      1. 7.1.1 Device Configurability
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Overvoltage (OV) Status
      2. 7.3.2 Undervoltage (UV) Status
      3. 7.3.3 Overcurrent in Charge (OCC) Status
      4. 7.3.4 Overcurrent in Discharge (OCD) and Short Circuit in Discharge (SCD) Status
      5. 7.3.5 Overtemperature (OT) Status
      6. 7.3.6 Charge and Discharge Driver
      7. 7.3.7 CTR for FET Override and Device Shutdown
      8. 7.3.8 CTR for PTC Connection
      9. 7.3.9 ZVCHG (0V Charging)
    4. 7.4 Device Functional Modes
      1. 7.4.1 Power Modes
        1. 7.4.1.1 Power-On-Reset (POR)
        2. 7.4.1.2 NORMAL Mode
        3. 7.4.1.3 FAULT Mode
        4. 7.4.1.4 SHUTDOWN Mode
  9. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Test Circuits for Device Evaluation
      2. 8.1.2 Test Circuit Diagrams
      3. 8.1.3 Using CTR as FET Driver On/Off Control
    2. 8.2 Typical Applications
      1. 8.2.1 BQ298xx Configuration 1: System-Controlled Reset/Shutdown Function
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Selection of Power FET
        4. 8.2.1.4 Application Curves
      2. 8.2.2 BQ298xx Configuration 2: CTR Function Disabled
      3. 8.2.3 BQ298xx Configuration 3: PTC Thermistor Protection
  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 第三方产品免责声明
    2. 11.2 接收文档更新通知
    3. 11.3 支持资源
    4. 11.4 Trademarks
    5. 11.5 静电放电警告
    6. 11.6 术语表
  13. 12Revision History
  14. 13Mechanical, Packaging, and Orderable Information

7.3.4 Overcurrent in Discharge (OCD) and Short Circuit in Discharge (SCD) Status

The BQ298xx device detects a current fault by monitoring the voltage drop across an external sense resistor (RSNS) between the CS and VSS pins. The device applies the same method to detect OCD and SCD faults and applies the same recovery scheme to release the OCD and SCD faults.

The device detects an OCD fault when (VCS – VSS) > OCD threshold (+VOC). If this condition exists for longer than the OCD delay (tOC), the DSG output is driven to VFETOFF to turn off the DSG FET. The SCD detection is similar to OCD, but uses the SCD threshold (VSCD) and SCD delay (tSCD) time.

During an OCD or SCD state, the device turns on the recovery detection circuit. An internal current sink (IPACK – VDD) is connected between the PACK and VDD pins, and the device consumes IOC_REC during the OCD and SCD fault until recovery is detected.

The OCD or SCD status is released and the DSG output rises to HIGH, that is VDSG = VDD × (1 + AFETON), if (VBAT – VPACK) < 400mV, indicating a discharge load is removed.