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  • All products
  • CO₂ sensors
  • STC31

STC31-C

New

CO₂ accuracy of ±(0.2 - 2.0 vol%) @0-100 vol%

The STC31-C is a chip-sized gas concentration sensor for high range, accurate CO₂measurements 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-C 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-C 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.

Distributor listContact sales

Specification

CO₂
Specified CO₂ Measurement Range
0 - 100
0 - 100vol %
Accuracy
±0.2 vol % ±2.0 %m.v.
±0.2 vol % ±2.0 %m.v.
Response time (τ63%)
0.5
0.5s
Temperature stability
0.02
0.02vol%/°C
Generic
Supply voltage
2.7 - 5.5

Downloads

Datasheet STC31-C

09/2025

File

994.6 KB

Datasheet09/2025PDF994.6 KB
Design guide STC31-C

09/2024

File

1.0 MB

Application note09/2024PDF1.0 MB
Handling and assembly guide STC31

06/2024

File

284.3 KB

Guide06/2024PDF284.3 KB
Arduino driver STC31

Link

SoftwareLink
Embedded driver STC31

Link

SoftwareLink
Raspberry Pi driver STC31

Link

SoftwareLink
SEK-ControlCenter (all devices)

Link

SoftwareLink
STEP file STC31/STC31-C

01/2023

File

1.5 MB

Drawings/CAD01/2023STEP1.5 MB
RoHS, REACH and Hal-Free declaration Thermal Conductivity Sensor

12/2025

File

94.5 KB

Certificate12/2025PDF94.5 KB
Carbon dioxide product flyer Japanese

09/2025

File

1.2 MB

Flyer09/2025PDF1.2 MB
2.7 - 5.5
V
Average supply current
50
50uA
Max. supply current
5
5mA
Interfaces
I²C
I²C
Size (LxWxH)
3.5 x 3 x 1
3.5 x 3 x 1mm
Packaging size
400
400pcs (Tray)

Sensor evaluation

Buy the following products to evaluate this sensor

NameDescriptionSeriesCategory
SEK-STC31-CCO₂ evaluation kit STC31-CSEK-STC31CO₂ sensors

SEK-STC31-C

CO₂ evaluation kit STC31-C

SEK-STC31

CO₂ sensors

Download the respective viewer software to start measuring

Go to download center

Start testing our sensors fast and easy with the evaluation kits

How to get started

Smart sensors for your application

Sensirion's sensor solutions are used in a wide range of applications and markets. Our reliable environmental and flow sensors improve energy efficiency, increase health and ensure safety and comfort.

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