Product description
Adafruit SCD-40 – True CO₂ Sensor with Temperature and Humidity Measurement. Adafruit’s SCD-40 is a compact, high-quality sensor that measures the true carbon dioxide concentration in air (CO₂) using photoacoustic technology, along with integrated temperature and relative humidity sensing. The SCD40 sensor from Sensirion is designed to provide reliable readings rather than approximating CO₂ based on VOC levels. Mounted on a breakout board with an onboard regulator and level shifter, it is easy to integrate with microcontroller and single-board computer platforms (Arduino, ESP32, Raspberry Pi, etc.).
Functions and Features:
- Measurement principle: Photoacoustic CO₂ sensor (true CO₂ measurement)
- CO₂ measurement range: 400 to 2000 ppm
- Accuracy: ±(50 ppm + 5% of reading)
- Current consumption: 17 mA (with 5 s measurement interval) / 0.5 mA (with 5 min measurement interval)
- Interface / connection: I²C (address 0x62) with two Qwiic connectors, or pin header (included but not soldered)
- Supply voltage: 3.3 - 5 V (integrated regulator and level shifter)
- Dimensions: 25.5 x 22.8 x 7.7 mm
- Calibration: Fully calibrated and linearized at delivery
Benefits:
- True CO₂ measurement: The sensor provides direct CO₂ readings instead of estimating values from volatile organic compounds (VOCs)
- Easy integration: Thanks to Qwiic (STEMMA QT) connectivity, the sensor can be connected without soldering and easily chained with other sensors
- Flexible supply voltage: 3.3 – 5 V power input with onboard regulator and level shifter enables use in projects with different logic levels
- Low standby current: With longer measurement intervals, the sensor can operate down to 0.5 mA, ideal for battery-powered systems
- Temperature and humidity sensing: Provides valuable complementary data for calibration, compensation, or environmental monitoring
Typical Applications:
- Indoor air quality monitoring
- Ventilation control (HVAC)
- Climate and greenhouse projects
- Research and educational projects
- IoT air quality sensors
Integration and Support:
Adafruit provides ready-to-use libraries and examples for Arduino and CircuitPython, allowing quick setup for measurement and data collection. Documentation, wiring diagrams, and tutorials are also available on Adafruit’s “Learn/Wiki” portal for connecting the sensor and processing the data.