SparkFun BME688 Environmental Sensor Breakout - Gas/Temp/Humidity/Pressure (Qwiic)

The BME688's integrated metal oxide (MOX) gas sensor is highly sensitive to a wide range of volatile organic compounds (VOCs), volatile sulfur compounds (VSCs), carbon monoxide (CO), and hydrogen (H2) at parts-per-billion (ppb) concentration levels. It provides a gas scan result as a digital index, with a standard scan time of approximately 10.8 seconds.

Yes, but you must account for logic level translation. The BME688 sensor IC operates from 1.71V to 3.6V. While the Qwiic bus on this breakout is designed for 3.3V, you can safely connect it to a 5V Arduino's I2C pins if you use a Qwiic cable with a built-in logic level converter or add an external level-shifting module to protect the sensor.

The board supports both protocols. I2C is the default, enabled via the onboard Qwiic connectors, using 7-bit addressing and two wires (SDA, SCL). SPI offers higher-speed data transfer using four dedicated lines (CS, SDO, SDI, SCK) and is selected by soldering a Jumper on the board. The choice depends on your microcontroller's available peripherals and required data rate.

The BME688 provides factory-calibrated digital outputs for temperature, humidity, and pressure. For gas sensing, it outputs a relative gas index or resistance ratio. While it does not require user calibration for basic operation, achieving quantitative gas concentration readings typically requires a baseline establishment and calibration routine in your specific environment due to the MOX sensor's sensitivity to ambient conditions.