Texas Instruments BQ76972 Battery Monitor

The bq76972 component reads a Texas Instruments BQ76972 battery monitor (datasheet, technical reference manual) over the I²C Bus. The default I²C address is 0x08.

The BQ76972 monitors 3 to 16 series cells and reports each cell voltage, the stack voltage and the temperature of its internal die and of thermistors on up to nine pins.

Configuration

# Example configuration entry
bq76972:
  id: bq76972_id
  stack_voltage:
    name: "Pack Total Voltage"
  internal_temperature:
    name: "Temperature - Internal"
  ts1_temperature:
    name: "Temperature - Pin TS1"
  cell_1_voltage:
    name: "Cell 1 Voltage"
  cell_2_voltage:
    name: "Cell 2 Voltage"
  # The top cell of a pack with fewer than 16 cells is wired to the VC16 input
  cell_16_voltage:
    name: "Cell 3 Voltage"

Configuration Variables

• id (Optional, ID): Manually specify the ID used for actions.
• address (Optional, int): The I²C address of the device. Defaults to 0x08.
• update_interval (Optional, Time): How often to poll the monitor. Defaults to 10s.
• crc_enabled (Optional, boolean): Use the CRC-protected I²C mode. Must match the mode the chip is configured for. Defaults to false.
• reg_disabled (Optional, boolean): Turn the chip’s REG0, REG1 and REG2 regulators off during setup. Leave this off when one of them powers the host or the I²C bus. Defaults to false.
• stack_voltage (Optional): The total stack voltage, in V. All options from Sensor.
• cell_1_voltage to cell_16_voltage (Optional): The voltage on each VC cell input, in V. The number is the input, not the cell’s position in the pack: a pack with fewer than 16 cells has its top cell wired to VC16, so that cell is cell_16_voltage, and the board’s wiring decides which other inputs carry a cell. Inputs shorted to the cell below read 0 and are not published. All options from Sensor.
• internal_temperature (Optional): The die temperature, in °C. All options from Sensor.
• cfetoff_temperature, dfetoff_temperature, alert_temperature, ts1_temperature, ts2_temperature, ts3_temperature, hdq_temperature, dchg_temperature, ddsg_temperature (Optional): The temperature of a thermistor on that pin, in °C. Configuring one of these sets the pin up as a thermistor input during setup; TS1 is a thermistor input by default. All options from Sensor.

bq76972.program_i2c_address Action

Writes a new I²C address into the chip’s data memory and switches to it. The address is held in the chip’s RAM: it survives a reboot of the ESP but reverts to the default when the chip loses power, so address in the configuration must match whichever address the chip currently answers to. After an ESP-only reboot the chip still answers at the programmed address and setup at the configured one fails; either power-cycle the chip or set address to the programmed value. A permanent change needs the address programmed into the chip’s OTP memory with the manufacturer’s tools.

button:
  - platform: template
    name: "Program BQ76972 Address"
    on_press:
      - bq76972.program_i2c_address:
          id: bq76972_id
          address: 0x09

• id (Optional, ID): The ID of the bq76972 component.
• address (Required, int, templatable): The new I²C address.

See Also

• I²C Bus
• Sensor Component