CO2 Sensor STC31
The most effective way to measure high CO2 concentrations
The STC31 is a chip-sized gas concentration sensor for high range, accurate CO2 measurements designed for high-volume production.
The sensor is based on a revolutionized thermal conductivity measurement principle, which results in superior repeatability and long-term stability. This makes the STC31 the perfect choice for applications where reliability is key. Thermal conductivity technology has an ultra-low power consumption, even compared to low-power optical sensor. This makes it the ideal choice for battery operated applications, delivering top-performance at an absolute minimal power budget.
The STC31 features a digital I2C interface, which makes it easy to connect directly to a microprocessor. The outstanding performance of these sensors is based on Sensirion’s patented CMOSens® Technology, which combines the sensor element, signal processing and digital calibration on a small CMOS chip. The well-proven CMOS technology is perfectly suited for high-quality mass production and is the ideal choice for demanding and cost-sensitive OEM applications.
Sensor Specifications
| Concentration Specifications | |
|---|---|
| Calibrated for | CO2 in N2 and CO2 in air |
| Measurement range | 0 to 100 vol% |
| Accuracy | < 0.5 vol% (+3% of m.v.) |
| Repeatability | 0.2 vol% |
| Resolution | 16 bit |
| Temperature Specifications | |
| Measurement range | -20 to 85 °C |
| Resolution | 16 bit |
| Accuracy | 0.5 °C (10 °C to 50 °C) 1.5 °C (-20 °C to 85 °C) |
| Repeatability | 0.1 °C |
| Electrical Specifications | |
| Supply voltage | 2.7 – 5.5 V |
| Max. supply current | 5 mA |
| Power consumption (@1 measurement per minute) | 15 µW |
How you benefit from our technology
| Technology | Benefit |
|---|---|
| CMOSens® Technology designed for mass production | Enables high-volume applications due to unprecedented price-performance ratio that scales with quantities |
| Many years of experience in the medical and automotive industries | Proven and reliable quality |
| Robust and no drift over lifetime | Reliable sensor output over product lifetime |
| On-chip humidity compensation | Worry-free operation at high humidity |
| Ultra-low power consumption | Longer battery life and cost savings |
| Small chip-sized package (3.5mm x 3mm x 1 mm) | Easy to integrate in existing design and portable devices |
| Fully calibrated digital output with I2C interface | Easy hassle-free integration |
| Reflow solderable | Fast, automated and low-cost assembly |
How to reduce food waste?
Sensing CO2, Humidity and Temperature in Cold Chain Logistics
The Food and Agriculture Organization of the United Nations has found that one third of all food is wasted. For fruits and vegetables, it is even more tremendous as 45% of all fresh products go to waste. To achieve a reduction of food waste it is crucial to consider the entire supply chain from farm to fork. Many fruits and vegetables, such as bananas, are transported and stored in a controlled atmosphere (CA) to preserve freshness. CA parameters are carbon dioxide (CO2) as well as humidity and temperature (RH/T).
Click here to learn more about our sensor solutions for food transportation.
Test our environmental sensors with Sensirion’s evaluation kit
With plug-and-play hardware, user-friendly viewer software and compatibility with all environmental sensors, SEK-Environmental Sensing makes evaluation easier and faster than ever before. This allows customers to focus on developing innovative sensor applications.
CMOSens® Technology for Thermal Conductivity
The STC31 measures the thermal conductivity (TC) of a gas. The measurement takes place inside the sensor cavity, which is protected from the environment by a gas-permeable membrane. Inside the cavity there are a heater and a temperature sensor. The heater heats up the gas and the temperature sensor measures how much of that heat is being transferred. The higher the TC of the gas, the more heat is transferred from the heater to the temperature sensor.
CO2 has a lower TC than air. Therefore, a decrease in TC signals a rise in CO2. Building on our extensive knowledge of micro-thermal flow sensors, we developed a gas model at Sensirion to quantify exactly what the CO2 concentration is. This all happens on the chip itself, allowing the STC31 to conveniently outputs a CO2 concentration.
CO2 Sensor SCD40 for indoor air quality measurements
The SCD40 represents the first CO2 sensor for indoor air quality measurements in miniature format, which impresses with a space requirement of only one cubic centimeter. This disruptive innovation is based on Sensirion's PASens® Technology and combines minimum size with maximum performance. The SCD40 opens up numerous new possibilities for integration and application. Because of its unmatched size and its unprecedented price-performance ratio, the SCD40 is the sensor of choice for today’s and future CO2 sensing markets such as IoT, automotive, HVAC, appliances and consumer goods.
Click here to learn more about the SCD40.
Environmental Sensing
Environmental conditions have a major impact on our well-being, comfort, and productivity. Sensirion’s sensor solutions provide detailed and reliable data on key environmental parameters such as humidity, temperature, volatile organic compounds (VOCs), particulate matter (PM2.5), and CO2. Environmental Sensing opens up new possibilities to create smarter devices that improve our comfort and well-being as well as increase energy efficiency in a wide variety of applications.
We accompany you through the entire product development process, from the initial idea to product launch and beyond. Our expertise ranges from prototype construction, design-in support and use-case development to inline testing at the mass production stage.
