Temperature Sensor

BME688
Digital low power gas, pressure, temperature & humidity sensor with AI

The BME688 is the first gas sensor with Artificial Intelligence (AI) and integrated high-linearity and high-accuracy
pressure, humidity and temperature sensors. It is housed in a robust yet compact 3.0 x 3.0 x 0.9 mm3 package
and especially developed for mobile & connected applications where size and low power consumption are critical
requirements. The gas sensor can detect Volatile Organic Compounds (VOCs), volatile sulfur compounds (VSCs)
and other gases such as carbon monoxide and hydrogen in the part per billion (ppb) range.
Additionally to all features of the BME680, the BME688 has a gas scanner function. In standard configuration, the
presence of VSCs is being detected as indicator for e.g. bacteria growth. And the gas scanner can be customized
with respect to sensitivity, selectivity, data rate and power consumption as well. The BME AI-Studio tool enables
customers to train the BME688 gas scanner on their specific application, like in home appliances, IoT products
or Smart Home.

Typical applications
 Indoor and outdoor air quality measurement
 Bad breath or spoiled food detection based on the measurement of volatile sulfur compounds, which are
an indicator of bacteria growth
 Detection of unusual gases and smells, which might indicate for instance a leakage or fire
 Diaper state detection, e.g. for baby care
 Early detection of odors & bad smells
 Wildfire detection

Target Devices
 Handsets such as mobile phones, tablet PCs, GPS devices
 Wearables e.g. smart watches or connected sensors
 Mobile / care devices like toothbrushes or breath checkers
 Smart home devices, e.g. smart speakers, connected sensors or lamps
 Room climate sensors & weather stations
 Home appliances
 Gaming, e.g. flying toys
 Connected devices, for instance for asset tracking or surveillance
 Sensor networks / sensor nodes

Key features
 Package 3.0 mm x 3.0 mm x 0.93 mm metal lid LGA
 Digital interface I2C (up to 3.4 MHz) and SPI (3 and 4 wire, up to 10 MHz)
 Supply voltage VDD main supply voltage range: 1.71 V to 3.6 V
VDDIO interface voltage range: 1.2 V to 3.6 V
 Current consumption 2.1 μA at 1 Hz humidity and temperature
3.1 μA at 1 Hz pressure and temperature
3.7 μA at 1 Hz humidity, pressure and temperature
90 μA at ULP mode for p/h/T & air quality
0,9 mA at LP mode for p/h/T & air quality
3,9 mA in standard gas scan mode
0.09‒12 mA for p/h/T/gas in customized operation modes
0.15 μA in sleep mode

 Operating range -40‒+85 °C, 0‒100% r.H., 300‒1100 hPa
 The product is RoHS compliant, halogen-free, MSL1

Key parameters for gas sensor
 F1 score for H2S scanning 0.92
 Standard scan speed 10.8 s / scan
 Electric charge for standard scan 0.18 mAh (5 scans ~ 1 min)
 Power consumption < 0.1 mA in ultra-low power mode
 Output data processing Major direct outputs: Index for Air Quality (IAQ), bVOC- & CO2-equivalents (ppm),
Gas scan result (%) & Intensity level (all listed in Table 20: BSEC outputs)

Key parameters for humidity sensor
 Response time (τ0−63%) ~8 s
 Accuracy tolerance ±3% r.H.
 Hysteresis ±1.5% r.H.

Key parameters for pressure sensor
 RMS Noise 0.12 Pa, equiv. to 1.7 cm
 Offset temperature coefficient ±1.3 Pa/K, equiv. to ±10.9 cm at 1 °C temperature change