SLUSFQ8B December   2024  – June 2025 BQ2969T

PRODMIX  

  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
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Pin Details
        1. 7.3.1.1 Input Sense Voltage, Vx
        2. 7.3.1.2 Output Drive, OUT
        3. 7.3.1.3 Supply Input, VDD
        4. 7.3.1.4 Control / PTC Input Pin, CTL
        5. 7.3.1.5 Regulated Supply Output, REG
      2. 7.3.2 Overvoltage Sensing for OUT
      3. 7.3.3 Regulator Output Voltage
    4. 7.4 Device Functional Modes
      1. 7.4.1 NORMAL Mode
      2. 7.4.2 OVERVOLTAGE Mode
      3. 7.4.3 UNDERVOLTAGE Mode
      4. 7.4.4 CTL / OVERTEMPERATURE Mode
      5. 7.4.5 CUSTOMER TEST 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 Curves
      4. 8.2.4 CTL for PTC Thermistor Protection
      5. 8.2.5 CTL for External OUT Overdrive
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Third-Party Products Disclaimer
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

7.4.3 UNDERVOLTAGE Mode

The UNDERVOLTAGE mode is detected if any of the cell voltage across (V1–VSS), (V2–V1), (V3–V2), or (V4–V3) is below the VUVREG threshold for tUVDELAY time. In this mode, the regulated output is disabled. To return to NORMAL mode, all the cell voltages must be above (VUVREG + VUVHYS) and below VOV.

If the device is used in a system with fewer than 4 cells, Vn pin can be shorted to the (Vn – 1) pin. The device ignores any differential cell voltage below the VUVQUAL threshold for undervoltage detection.

Even when in the UNDERVOLTAGE mode, the device continues to regularly monitor the CTL pin voltage and each cell voltage, checking if CTL falls below VDD–VCTL or if any cell voltage exceeds the VOV threshold. If a condition occurs whereby a cell voltage is above VOV and another cell voltage is below VUVREG, such as can happen in a heavily imbalanced pack, then the OUT pin is activated and the regulator is disabled.