SLVT251 July   2026

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Key System Specifications
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
      1. 2.2.1 High-Voltage Stackable Architecture
      2. 2.2.2 Electrochemical Impedance Spectroscopy (EIS) Subsystem
      3. 2.2.3 EIS Synchronization Requirement
      4. 2.2.4 PWM Input as Crystal of the First BQ79826Z-Q1
      5. 2.2.5 Temperature Sensing and Multiplexer Network
      6. 2.2.6 Cell Balancing Circuit and Operation
      7. 2.2.7 MCU and System Control Architecture
      8. 2.2.8 Protection and On-Board Diagnostics
    3. 2.3 Highlighted Products
      1. 2.3.1 BQ79826Z-Q1
      2. 2.3.2 TMUX1308
      3. 2.3.3 TMP61
      4. 2.3.4 SN74LXC1T14
  9. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware Requirements
    2. 3.2 Software
    3. 3.3 Test Setup
    4. 3.4 Pack Test Results
      1. 3.4.1 Cell Voltage Reliability Test
      2. 3.4.2 EIS Measurement Repeatability
      3. 3.4.3 Pack EIS Measurement Nyquist Plot
      4. 3.4.4 Current Consumption per BQ79826Z-Q1
  10. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 BOM
      3. 4.1.3 PCB Layout Recommendations
    2. 4.2 Tools and Software
      1. 4.2.1 Tools
    3. 4.3 Documentation Support
    4. 4.4 Support Resources
    5.     Trademarks
  11. 5About the Author

Description

This reference design is a full cell temperature sensing and high cell-voltage accuracy Lithium-ion (Li-ion), lithium iron phosphate (LiFePO4) battery pack (52s and 104s). The design monitors each cell voltage, cell temperature, impedance, while supporting integrated electrochemical impedance spectroscopy (EIS) and robust daisy-chain communication. This design supports up to 1500V stackable energy storage systems. These features make this reference design applicable for high-capacity battery pack applications.