SLUUCJ0 November 2023 BQ76907
- 1
- Read This First
- 1 Introduction
- 2 Device Description
- 3 Device Configuration
- 4 Device Security
- 5 Measurement Subsystem
-
6 Protection
Subsystem
- 6.1 Protections Overview
- 6.2 Protection FET Drivers
- 6.3 Cell Overvoltage Protection
- 6.4 Cell Undervoltage Protection
- 6.5 Short Circuit in Discharge Protection
- 6.6 Overcurrent in Charge Protection
- 6.7 Overcurrent in Discharge 1 and 2 Protections
- 6.8 Current Protection Latch
- 6.9 CHG Detector
- 6.10 Overtemperature in Charge Protection
- 6.11 Overtemperature in Discharge Protection
- 6.12 Internal Overtemperature Protection
- 6.13 Undertemperature in Charge Protection
- 6.14 Undertemperature in Discharge Protection
- 6.15 Host Watchdog Protection
- 6.16 Cell Open Wire Detection
- 6.17 Voltage Reference Measurement Diagnostic Protection
- 6.18 VSS Measurement Diagnostic Protection
- 6.19 REGOUT Diagnostic Protection
- 6.20 LFO Oscillator Integrity Diagnostic Protection
- 6.21 Internal Factory Trim Diagnostic Protection
- 7 Device Status and Controls
- 8 Operational Modes
- 9 I2C Serial Communications
- 10Cell Balancing
-
11Commands and Subcommands
- 11.1 Direct Commands
- 11.2
Bit field Definitions for Direct Commands
- 11.2.1 Safety Alert A Register
- 11.2.2 Safety Status A Register
- 11.2.3 Safety Alert B Register
- 11.2.4 Safety Status B Register
- 11.2.5 Battery Status Register
- 11.2.6 Alarm Status Register
- 11.2.7 Alarm Raw Status Register
- 11.2.8 Alarm Enable Register
- 11.2.9 FET CONTROL Register
- 11.2.10 REGOUT CONTROL Register
- 11.2.11 DSG FET Driver PWM Control Register
- 11.2.12 CHG FET Driver PWM Control Register
- 11.3 Command-only Subcommands
- 11.4 Subcommands with Data
- 11.5 Bit field Definitions for Subcommands
-
12Data Memory
- 12.1 Calibration
- 12.2
Settings
- 12.2.1
Settings:Configuration
- 12.2.1.1 Settings:Configuration:Power Config
- 12.2.1.2 Settings:Configuration:REGOUT Config
- 12.2.1.3 Settings:Configuration:I2C Address
- 12.2.1.4 Settings:Configuration:I2C Config
- 12.2.1.5 Settings:Configuration:DA Config
- 12.2.1.6 Settings:Configuration:Vcell Mode
- 12.2.1.7 Settings:Configuration:Default Alarm Mask
- 12.2.1.8 Settings:Configuration:FET Options
- 12.2.1.9 Settings:Configuration:Charge Detector Time
- 12.2.2 Settings:Cell Balancing
- 12.2.3
Settings:Protection
- 12.2.3.1 Settings:Protection:Enabled Protections A
- 12.2.3.2 Settings:Protection:Enabled Protections B
- 12.2.3.3 Settings:Protection:DSG FET Protections A
- 12.2.3.4 Settings:Protection:CHG FET Protections A
- 12.2.3.5 Settings:Protection:Both FET Protections B
- 12.2.3.6 Settings:Protection:Body Diode Threshold
- 12.2.3.7 Settings:Protection:Cell Open Wire NORMAL Check Time
- 12.2.3.8 Settings:Protection:Cell Open Wire SLEEP Check Time
- 12.2.3.9 Settings:Protection:Host Watchdog Timeout
- 12.2.1
Settings:Configuration
- 12.3
Protections
- 12.3.1
Protections:Cell Voltage
- 12.3.1.1 Protections:Cell Voltage:Cell Undervoltage Protection Threshold
- 12.3.1.2 Protections:Cell Voltage:Cell Undervoltage Protection Delay
- 12.3.1.3 Protections:Cell Voltage:Cell Undervoltage Protection Recovery Hysteresis
- 12.3.1.4 Protections:Cell Voltage:Cell Overvoltage Protection Threshold
- 12.3.1.5 Protections:Cell Voltage:Cell Overvoltage Protection Delay
- 12.3.1.6 Protections:Cell Voltage:Cell Overvoltage Protection Recovery Hysteresis
- 12.3.2
Protections:Current
- 12.3.2.1 Protections:Current:Overcurrent in Charge Protection Threshold
- 12.3.2.2 Protections:Current:Overcurrent in Charge Protection Delay
- 12.3.2.3 Protections:Current:Overcurrent in Discharge 1 Protection Threshold
- 12.3.2.4 Protections:Current:Overcurrent in Discharge 1 Protection Delay
- 12.3.2.5 Protections:Current:Overcurrent in Discharge 2 Protection Threshold
- 12.3.2.6 Protections:Current:Overcurrent in Discharge 2 Protection Delay
- 12.3.2.7 Protections:Current:Short Circuit in Discharge Protection Threshold
- 12.3.2.8 Protections:Current:Short Circuit in Discharge Protection Delay
- 12.3.2.9 Protections:Current:Latch Limit
- 12.3.2.10 Protections:Current:Recovery Time
- 12.3.3
Protections:Temperature
- 12.3.3.1 Protections:Temperature:Overtemperature in Charge Protection Threshold
- 12.3.3.2 Protections:Temperature:Overtemperature in Charge Protection Delay
- 12.3.3.3 Protections:Temperature:Overtemperature in Charge Protection Recovery
- 12.3.3.4 Protections:Temperature:Undertemperature in Charge Protection Threshold
- 12.3.3.5 Protections:Temperature:Undertemperature in Charge Protection Delay
- 12.3.3.6 Protections:Temperature:Undertemperature in Charge Protection Recovery
- 12.3.3.7 Protections:Temperature:Overtemperature in Discharge Protection Threshold
- 12.3.3.8 Protections:Temperature:Overtemperature in Discharge Protection Delay
- 12.3.3.9 Protections:Temperature:Overtemperature in Discharge Protection Recovery
- 12.3.3.10 Protections:Temperature:Undertemperature in Discharge Protection Threshold
- 12.3.3.11 Protections:Temperature:Undertemperature in Discharge Protection Delay
- 12.3.3.12 Protections:Temperature:Undertemperature in Discharge Protection Recovery
- 12.3.3.13 Protections:Temperature:Internal Overtemperature Protection Threshold
- 12.3.3.14 Protections:Temperature:Internal Overtemperature Protection Delay
- 12.3.3.15 Protections:Temperature:Internal Overtemperature Protection Recovery
- 12.3.1
Protections:Cell Voltage
- 12.4 Power
- 12.5 Security
- 12.6 Data Memory Summary
- 13Revision History
5.3 Internal Temperature Measurement
The BQ76907 device integrates the capability to measure its internal die temperature by digitizing the difference between two internal transistor base-emitter voltages. This voltage difference is measured periodically as part of the measurement loop and is processed to provide a temperature value using the 0x28 Int Temperature() command in units of °C. This resulting value is used by several protections and decisions within the device, such as the Internal Overtemperature Protection, internal overtemperature shutdown (based on Power:Shutdown:Shutdown Temperature, and cell balancing (based on Settings:Cell Balancing:Max Internal Temp).
The calculation of temperature is performed as follows using the Calibration:Temperature:Int Temp Offset and Calibration:Temperature:Int Temp Gain configuration parameters:
