SLUSFC9
December 2023
BQ76972
PRODUCTION DATA
1
1
Features
2
Applications
3
Description
4
Device Comparison Table
5
Pin Configuration and Functions
6
Specifications
6.1
Absolute Maximum Ratings
6.2
ESD Ratings
6.3
Recommended Operating Conditions
6.4
Thermal Information BQ76952
6.5
Supply Current
6.6
Digital I/O
6.7
LD Pin
6.8
Precharge (PCHG) and Predischarge (PDSG) FET Drive
6.9
FUSE Pin Functionality
6.10
REG18 LDO
6.11
REG0 Pre-regulator
6.12
REG1 LDO
6.13
REG2 LDO
6.14
Voltage References
6.15
Coulomb Counter
6.16
Coulomb Counter Digital Filter (CC1)
6.17
Current Measurement Digital Filter (CC2)
6.18
Current Wake Detector
6.19
Analog-to-Digital Converter
6.20
Cell Voltage Measurement Accuracy
6.21
Cell Balancing
6.22
Cell Open Wire Detector
6.23
Internal Temperature Sensor
6.24
Thermistor Measurement
6.25
Internal Oscillators
6.26
High-side NFET Drivers
6.27
Comparator-Based Protection Subsystem
6.28
Timing Requirements - I2C Interface, 100kHz Mode
6.29
Timing Requirements - I2C Interface, 400kHz Mode
6.30
Timing Requirements - HDQ Interface
6.31
Timing Requirements - SPI Interface
6.32
Interface Timing Diagrams
6.33
Typical Characteristics
7
Detailed Description
7.1
Overview
7.2
Functional Block Diagram
7.3
BQ76972 Device Versions
7.4
Diagnostics
7.5
Device Configuration
7.5.1
Commands and Subcommands
7.5.2
Configuration Using OTP or Registers
7.5.3
Device Security
7.5.4
Scratchpad Memory
7.6
Measurement Subsystem
7.6.1
Voltage Measurement
7.6.1.1
Voltage Measurement Schedule
7.6.1.2
Usage of VC Pins for Cells Versus Interconnect
7.6.1.3
Cell 1 Voltage Validation During SLEEP Mode
7.6.2
General Purpose ADCIN Functionality
7.6.3
Coulomb Counter and Digital Filters
7.6.4
Synchronized Voltage and Current Measurement
7.6.5
Internal Temperature Measurement
7.6.6
Thermistor Temperature Measurement
7.6.7
Factory Trim of Voltage ADC
7.6.8
Cell Voltage Measurement Accuracy
7.6.8.1
Fixed Offset Adjustment
7.6.8.2
Cell Offset Calibration
7.6.9
Voltage Calibration (ADC Measurements)
7.6.10
Voltage Calibration (COV and CUV Protections)
7.6.11
Current Calibration
7.6.12
Temperature Calibration
7.7
Primary and Secondary Protection Subsystems
7.7.1
Protections Overview
7.7.2
Primary Protections
7.7.3
Secondary Protections
7.7.4
High-Side NFET Drivers
7.7.5
Protection FETs Configuration and Control
7.7.5.1
FET Configuration
7.7.5.2
PRECHARGE and PREDISCHARGE Modes
7.7.6
Load Detect Functionality
7.8
Device Hardware Features
7.8.1
Voltage References
7.8.2
ADC Multiplexer
7.8.3
LDOs
7.8.3.1
Preregulator Control
7.8.3.2
REG1 and REG2 LDO Controls
7.8.4
Standalone Versus Host Interface
7.8.5
Multifunction Pin Controls
7.8.6
RST_SHUT Pin Operation
7.8.7
CFETOFF, DFETOFF, and BOTHOFF Pin Functionality
7.8.8
ALERT Pin Operation
7.8.9
DDSG and DCHG Pin Operation
7.8.10
Fuse Drive
7.8.11
Cell Open Wire
7.8.12
Low Frequency Oscillator
7.8.13
High Frequency Oscillator
7.9
Device Functional Modes
7.9.1
Overview
7.9.2
NORMAL Mode
7.9.3
SLEEP Mode
7.9.4
DEEPSLEEP Mode
7.9.5
SHUTDOWN Mode
7.9.6
CONFIG_UPDATE Mode
7.10
Serial Communications Interface
7.10.1
Serial Communications Overview
7.10.2
I2C Communications
7.10.3
SPI Communications
7.10.3.1
SPI Protocol
7.10.4
HDQ Communications
7.11
Cell Balancing
7.11.1
Cell Balancing Overview
8
Application and Implementation
8.1
Application Information
8.2
Typical Applications
8.2.1
Design Requirements (Example)
8.2.2
Detailed Design Procedure
8.2.3
Application Performance Plot
8.2.4
Calibration Process
8.3
Random Cell Connection Support
8.4
Startup Timing
8.5
FET Driver Turn-Off
8.6
Unused Pins
8.7
Power Supply Requirements
8.8
Layout
8.8.1
Layout Guidelines
8.8.2
Layout Example
9
Device and Documentation Support
9.1
Documentation Support
9.2
Support Resources
9.3
Trademarks
9.4
Electrostatic Discharge Caution
9.5
Glossary
10
Revision History
11
Mechanical, Packaging, Orderable Information
Package Options
Mechanical Data (Package|Pins)
PFB|48
MTQF019B
Thermal pad, mechanical data (Package|Pins)
Orderable Information
slusfc9_oa
slusfc9_pm
1
Features
Battery monitoring capability for 3-series to 16-series cells
High accuracy cell voltage measurement of ±3.0 mV
Integrated charge pump for high-side NFET protection with optional autonomous recovery
Extensive protection suite including voltage, temperature, current, and internal diagnostics
Two independent ADCs
Support for simultaneous current and voltage sampling
High-accuracy coulomb counter with input offset error < 1 µV (typical)
Wide-range current applications (±200-mV measurement range across sense resistor)
Integrated secondary chemical fuse drive protection
Autonomous or host-controlled cell balancing
Multiple power modes (typical battery pack operating range conditions)
NORMAL mode: 286 µA
Multiple SLEEP mode options: 24 µA to 41 µA
Multiple DEEPSLEEP mode options: 9 µA to 10 µA
SHUTDOWN mode: 1 µA
High-voltage tolerance of 85 V on cell connect and select additional pins
Tolerant of random cell attach sequence on production line
Support for temperature sensing using internal sensor and up to nine external thermistors
Integrated one-time-programmable (OTP) memory programmable by customers on production line
Communication options include 400-kHz I
2
C, SPI, and HDQ one-wire interface
Dual-programmable LDOs for external system usage
48-pin TQFP package (PFB)