CO2 sensor measures from 0 ppm to 10,000 ppm

Based on photoacoustic spectroscopy (PAS), the sensor uses a high-sensitivity MEMS microphone to detect the pressure change generated by CO₂ molecules within the sensor cavity. The result is a significantly miniaturised CO₂ sensor that offers space savings of more than 75% in end products compared to other CO₂ sensors on the market.

The sensor integrates a photoacoustic transducer — including detector, infrared source, and optical filter — plus a microcontroller for signal processing and algorithms and a MOSFET to drive the infrared source.

An integrated microcontroller converts the MEMS microphone output into a ppm reading, which is available either via the serial I²C, UART or PWM interface.

The sensor measures a range from 0 ppm to 10,000 ppm with an accuracy of ± 30 ppm or ±3% of the reading.

Direct ppm readings, surface mounting capability, and simple design allow for fast integration into low- and high-volume applications such as smart home and building automation designs, demand-controlled ventilation, air purifiers, thermostats, weather stations, and personal assistants.