SLUSAM9E
July 2011 – April 2020
BQ76925
PRODUCTION DATA.
1
Features
2
Applications
3
Description
Device Images
Simplified Schematic
4
Revision History
5
Description (Continued)
6
Pin Configuration and Functions
Pin Functions
7
Specifications
7.1
Absolute Maximum Ratings
7.2
ESD Ratings
7.3
Recommended Operating Conditions
7.4
Thermal Information
7.5
Electrical Characteristics: Supply Current
7.6
Internal Power Control (Startup and Shutdown)
7.7
3.3-V Voltage Regulator
7.8
Voltage Reference
7.9
Cell Voltage Amplifier
7.10
Current Sense Amplifier
7.11
Overcurrent Comparator
7.12
Internal Temperature Measurement
7.13
Cell Balancing and Open Cell Detection
7.14
I2C Compatible Interface
7.15
Typical Characteristics
8
Detailed Description
8.1
Overview
8.2
Functional Block Diagram
8.3
Feature Description
8.3.1
Internal LDO Voltage Regulator
8.3.2
ADC Interface
8.3.2.1
Reference Voltage
8.3.2.1.1
Host ADC Calibration
8.3.2.2
Cell Voltage Monitoring
8.3.2.2.1
Cell Amplifier Headroom Under Extreme Cell Imbalance
8.3.2.2.2
Cell Amplifier Headroom Under BAT Voltage Drop
8.3.2.3
Current Monitoring
8.3.2.4
Overcurrent Monitoring
8.3.2.5
Temperature Monitoring
8.3.2.5.1
Internal Temperature Monitoring
8.3.3
Cell Balancing and Open Cell Detection
8.4
Device Functional Modes
8.4.1
Power Modes
8.4.1.1
POWER ON RESET (POR)
8.4.1.2
STANDBY
8.4.1.3
SLEEP
8.5
Programming
8.5.1
Host Interface
8.5.1.1
I2C Addressing
8.5.1.2
Bus Write Command to BQ76925
8.5.1.3
Bus Read Command from BQ76925 Device
8.6
Register Maps
8.6.1
Register Descriptions
9
Application and Implementation
9.1
Application Information
9.1.1
Recommended System Implementation
9.1.1.1
Voltage, Current, and Temperature Outputs
9.1.1.2
Power Management
9.1.1.3
Low Dropout (LDO) Regulator
9.1.1.4
Input Filters
9.1.1.5
Output Filters
9.1.2
Cell Balancing
9.2
Typical Application
9.2.1
Design Requirements
9.2.2
Detailed Design Procedure
9.2.3
Application Curves
10
Power Supply Recommendations
11
Layout
11.1
Layout Guidelines
11.2
Layout Example
12
Device and Documentation Support
12.1
Documentation Support
12.1.1
Related Documentation
12.2
Receiving Notification of Documentation Updates
12.3
Support Resources
12.4
Trademarks
12.5
Electrostatic Discharge Caution
12.6
Glossary
13
Mechanical, Packaging, and Orderable Information
1
Features
Analog interface for host cell measurement
Cell input MUX, level shifter, and scaler
1.5-/ 3.0-V low-drift, calibrated reference allows accurate analog-to-digital conversions
Analog interface for host current measurement
Variable gain current sense amplifier capable of operation with 1-mΩ sense resistor
Switchable thermistor bias output for host temperature measurements
Overcurrent comparator with dynamically adjustable threshold
Alerts host to potential overcurrent faults
Wakes up host on load connect
Integrated cell balancing FETs
Individual host control
50 mA per cell balancing current
Supports cell sense-line open wire detection
Integrated 3.3-V regulator for powering micro-controller or LEDs
I
2
C interface for host communications
Optional packet CRC for robust operation
Supply voltage range from 4.2 V to 26.4 V
Low power consumption
40 µA typical in NORMAL mode
1.5 µA maximum in SLEEP mode
20-pin TSSOP or 24-pin VQFN package