Infineon XENSIV PAS CO2 sensor

Infineon Technologies has released the XENSIV PAS CO₂ sensor. 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 miniaturised CO₂ sensor that offers space savings of more than 75% space in end products compared to other CO₂ sensors on the market, the company claims.

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. The 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.

The sensor’s 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.