SLVT251
July 2026
1
Description
Resources
Features
Applications
6
1
System Description
1.1
Key System Specifications
2
System Overview
2.1
Block Diagram
2.2
Design Considerations
2.2.1
High-Voltage Stackable Architecture
2.2.2
Electrochemical Impedance Spectroscopy (EIS) Subsystem
2.2.3
EIS Synchronization Requirement
2.2.4
PWM Input as Crystal of the First BQ79826Z-Q1
2.2.5
Temperature Sensing and Multiplexer Network
2.2.6
Cell Balancing Circuit and Operation
2.2.7
MCU and System Control Architecture
2.2.8
Protection and On-Board Diagnostics
2.3
Highlighted Products
2.3.1
BQ79826Z-Q1
2.3.2
TMUX1308
2.3.3
TMP61
2.3.4
SN74LXC1T14
3
Hardware, Software, Testing Requirements, and Test Results
3.1
Hardware Requirements
3.2
Software
3.3
Test Setup
3.4
Pack Test Results
3.4.1
Cell Voltage Reliability Test
3.4.2
EIS Measurement Repeatability
3.4.3
Pack EIS Measurement Nyquist Plot
3.4.4
Current Consumption per BQ79826Z-Q1
4
Design and Documentation Support
4.1
Design Files
4.1.1
Schematics
4.1.2
BOM
4.1.3
PCB Layout Recommendations
4.2
Tools and Software
4.2.1
Tools
4.3
Documentation Support
4.4
Support Resources
Trademarks
5
About the Author
Design Guide
Up to 1500V Stackable Battery Management Unit Reference Design with Integrated EIS