Overview
The BQ7694002DBTR, part of the BQ76940 family, is a robust analog front-end (AFE) device designed by Texas Instruments for advanced battery management systems. This component is tailored for monitoring and protecting lithium-ion (Li-ion) and lithium-iron phosphate (Li-phosphate) battery packs, particularly those with up to 15 series cells or typical 48-V packs. The BQ76940 family is integral in high-power applications such as light electric vehicles, power tools, and uninterruptible power supplies.
Key Specifications
| Parameter | Description |
|---|---|
| Package | TSSOP (DBT) with 44 pins |
| Operating Temperature Range | -40°C to 85°C |
| Supply Voltage Absolute Maximum | Up to 108 V |
| Output Voltage Regulator | 2.5-V or 3.3-V |
| ADC Resolution | 14-bit for cell voltage and temperature, 16-bit for pack current (coulomb counter) |
| Thermistor Support | Directly supports up to three thermistors (103AT) |
| Interface | Simple I2C compatible interface (CRC option) |
| Cell Balancing | Integrated cell balancing FETs |
| FET Drivers | Charge and discharge low-side NCH FET drivers |
Key Features
- AFE Monitoring Features: Pure digital interface with internal ADCs measuring cell voltage, die temperature, and external thermistor.
- Hardware Protection Features: Overcurrent in discharge (OCD), short circuit in discharge (SCD), overvoltage (OV), undervoltage (UV), and secondary protector fault detection.
- Integrated Cell Balancing FETs: For balancing battery cells.
- Charge and Discharge FET Drivers: Low-side NCH FET drivers for charge and discharge control.
- Alert Interrupt: To host microcontroller for critical events.
- No EEPROM Programming Necessary: Settings are preconfigured and stored in EEPROM.
- Random Cell Connection Tolerant: Flexible connection options.
- Ultra-Low Power State: SHIP mode for reducing power consumption.
Applications
The BQ76940 is designed for use in various high-power applications, including:
- Light electric vehicles
- Power tools
- Uninterruptible power supplies (UPS)
Q & A
- What is the maximum number of series cells supported by the BQ76940?
The BQ76940 supports up to 15 series cells or typical 48-V packs.
- What types of battery chemistries can be managed by the BQ76940?
The BQ76940 can manage Li-ion, Li-iron phosphate, and other battery chemistries.
- What is the operating temperature range of the BQ76940?
The operating temperature range is -40°C to 85°C.
- Does the BQ76940 require EEPROM programming?
No, the BQ76940 does not require EEPROM programming as settings are preconfigured and stored in EEPROM.
- What protection features are included in the BQ76940?
The BQ76940 includes overcurrent in discharge (OCD), short circuit in discharge (SCD), overvoltage (OV), undervoltage (UV), and secondary protector fault detection.
- How does the BQ76940 communicate with the host controller?
The BQ76940 communicates through a simple I2C compatible interface (CRC option).
- What is the resolution of the ADCs in the BQ76940?
The BQ76940 has 14-bit ADCs for cell voltage and temperature, and a 16-bit ADC for pack current (coulomb counter).
- Does the BQ76940 support multiple thermistors?
- What is the purpose of the SHIP mode in the BQ76940?
The SHIP mode allows the device to enter an ultra-low power state to reduce power consumption.
- What types of FET drivers are integrated into the BQ76940?
The BQ76940 includes charge and discharge low-side NCH FET drivers.
