SparkFun Indoor Air Quality Combo Sensor - SCD41, SEN55 (Qwiic)

Get a complete, real-time snapshot of your surrounding environment with the SparkFun Indoor Air Quality Combo Sensor. This board pairs two specialised environmental sensors from Sensirion, the SCD41 and the SEN55, into a single, high-accuracy monitoring station. Instead of chaining multiple separate breakout boards to track different atmospheric variables, this all-in-one board measures carbon dioxide (CO₂), Volatile Organic Compounds (VOCs), Nitrogen Oxides (NO_x), particulate matter, temperature, and relative humidity simultaneously!

Advanced Laser and Acoustic Sensing

By combining the two distinct hardware capabilities of the SCD41 and the SEN55, the SparkFun Indoor Air Quality Combo Sensor provides extensive data gathering capabilities while keeping your project footprint as minimal as possible.

• Photoacoustic CO2 Sensing: The SCD41 utilizes narrowband infrared light and an internal microphone to measure CO₂ concentrations up to 40,000ppm, automatically calibrating over a 7-day period to maintain long-term precision.
• Full-Spectrum Particulate Tracking: The SEN55 optical sensor node detects PM1.0, PM2.5, PM4, and PM10 particles from 0 to 1,000 µg/m³, leveraging internal design features to ensure an operational lifetime of over 10 years.
• Petrol Index Monitoring: Instantly read both VOC and NO_x indexes on a scale of 1 to 500 index points, fully supported by on-board humidity compensation algorithms to prevent environmental data drift.
• Streamlined Power System: An onboard step-up DC/DC boost converter automatically handles the SEN55's higher 4.5V power requirements, allowing both sensors to run safely from a single standard 3.3V power source.

Please keep in mind that while we kept this board as small as possible, given the size of the sensors, it is far larger than the typical Qwiic breakout. The SparkFun Indoor Air Quality Combo Sensor measures 3.25 x 1.75 x 1.00 in.

Communication for this sensor is handled entirely over a plug-and-play Qwiic connection, delivering data over I²C communication without any mandatory soldering. For custom prototyping layouts or breadboard integration, the board also breaks out standard 0.1-inch-spaced pins, along with jumper options to change I²C addresses or switch the interface to SPI.

• Schematic
• KiCad Files
• Board Dimensions
• Hookup Guide
• Datasheets
  • SCD4x
  • SEN5x
•  Libraries
  • Sensirion Arduino Core
  • SparkFun SCD4x Arduino Library
  • Sensirion SEN5x Arduino Library
• Qwiic Information Page
• Sensirion CMOSens^® Technology
• GitHub Hardware Repo