The 7Semi SCD40 CO2, Temperature and Humidity Sensor Breakout Board provides reliable indoor air quality monitoring in a compact form. It uses Sensirion’s PASens® photoacoustic technology to measure actual CO2 levels. The sensor also provides temperature and relative humidity readings. An onboard voltage regulator and I2C level shifting support easy connection to 3.3V and 5V controllers. Dual Qwiic-compatible connectors allow multiple I2C modules to be connected in a chain. It is ideal for HVAC systems, classrooms, offices, greenhouses and IoT projects.
Important power note: When powering the board through VCC, the 3V3 pin acts as the regulated 3.3V output with 200mA current rating . Alternatively, the board can be powered directly through the 3V3 pin. Do not apply power to both VCC and 3V3 at the same time.

Key Features
- Measures CO2, temperature and relative humidity
- Practical CO2 measurement range: 400 ppm to 40,000 ppm
- CO2 accuracy: ±(50 ppm + 5% of reading) from 400 ppm to 2,000 ppm
- I2C interface with onboard bidirectional logic-level shifting
- Dual Qwiic-compatible connectors for plug-and-play and daisy-chain connections
- Automatic self-calibration and forced recalibration support
- Compatible with Arduino, ESP32, STM32
Calibration Certificate
A calibration certificate is available for the sensor. To request the certificate, please email us the sensor serial number, and we will share the corresponding calibration certificate.
Items Included
- 1 × 7Semi SCD43 Breakout Board (ES-12295)
- 1 × Pin Header
Note: The Qwiic cable is not included and must be purchased separately.
- SCD40 Datasheet
- User Guide and Sample Code etc.
- 7Semi SCD40 Breakout 3D Step File
- 7Semi SCD40 Breakout DXF File
- Sensirion I2C SCD4x Arduino Library (Library for the SCD4X sensor family by Sensirion Enables you to use the SCD40 and SCD41 sensors via I2C.)
- Category of product:
- Digital Enviroment sensor
- Communication Interface:
- I2C (Default Address: 0x62)
- Supply Voltage (VCC):
- 3.6V to 5.5V
- Operational Temprature in °C:
- -10C TO +60C
- Temperature Accuracy:
- ±0.8°C typical from 15°C to 35°C
- Operational humidity:
- 0%RH to 95%RH, non-condensing
- Humidity Accuracy:
- ±6%RH typical from 15%RH to 90%RH
- CO2 Measurement Range:
- 400ppm to 40,000ppm
- CO2 Accuracy:
- ±(50 ppm + 5% of reading) 400 ppm to 2,000 ppm
- Dimensions:
- 30mm x 22mm x 7.83mm
- _3d_glb:
- https://7semi.com/content/3d-files/dfx_step/10172.glb