SLUSE36J July   2021  – November 2023 BQ77216

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Description (continued)
  6. Device Comparison Table
  7. Pin Configuration and Functions
  8. 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 DC Characteristics
    6. 7.6 Timing Requirements
  9. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Voltage Fault Detection
      2. 8.3.2 Open-Wire Fault Detection
      3. 8.3.3 Temperature Fault Detection
      4. 8.3.4 Oscillator Health Check
      5. 8.3.5 Sense Positive Input for Vx
      6. 8.3.6 Output Drive, COUT and DOUT
      7. 8.3.7 The LATCH Function
      8. 8.3.8 Supply Input, VDD
    4. 8.4 Device Functional Modes
      1. 8.4.1 NORMAL Mode
      2. 8.4.2 FAULT Mode
      3. 8.4.3 Customer Test Mode
  10. Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Design Requirements
      2. 9.1.2 Detailed Design Procedure
        1. 9.1.2.1 Cell Connection Sequence
    2. 9.2 Systems Example
  11. 10Power Supply Recommendations
  12. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  13. 12Device and Documentation Support
    1. 12.1 Third-Party Products Disclaimer
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Support Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  14. 13Revision History
  15. 14Mechanical, Packaging, and Orderable Information

Package Options

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

Open-Wire Fault Detection

In the BQ77216 device, each cell input is monitored independently to determine if the input is connected to a cell or not by applying a 50-μA pull down current to ground that is activated for 128 μs every 128 ms. If the device detects that Vn < Vn–1 – VOW V, then a timer is activated. When the timer expires, the COUT and DOUT pins go from an inactive to active state. The timer is reset if the cell input rises above or below the recovery threshold (VOW + VOW_HYS).