Sensirion SCD41
Photoacoustic NDIR CO₂ sensor with an extended specified range and single-shot operation.
Key Specifications
How Photoacoustic CO₂ Sensing Works
The sensor modulates infrared light near a CO₂ absorption wavelength. When the gas absorbs the light, periodic heating creates a small pressure or acoustic signal. An acoustic detector measures the signal and the device’s electronics estimate carbon dioxide concentration, applying compensation and calibration as specified by the manufacturer.
Integration Considerations
Verify measurement conditions, automatic baseline correction requirements, installation environment, power peaks, bus communications, humidity and pressure effects, and manufacturer lifecycle status before product selection. Accuracy ranges should not be confused with digital reporting or output ranges.
Official Manufacturer Source
Product information and lifecycle status should be checked against the current manufacturer listing.
View SCD41 official product page →AirAlign is an independent technical information resource and is not affiliated with Sensirion. Specifications and product availability can change.
SCD41 — extended 5,000 ppm calibrated range and single-shot mode — model-specific datasheet review
These original manufacturer specifications are bounded to their stated measurement conditions. Output coding, calibrated precision, voltage domains, firmware and lifecycle status are not universal across variants.
| Property | Official model specification | Engineering limitation |
|---|---|---|
| CO₂ technology | Photoacoustic NDIR + RH/T on-chip | CO₂ ppm is a direct gas-specific sensor measurement, not VOC-derived eCO₂. |
| Specified measurement range | 400–5,000 ppm; digital output supports 0–40,000 ppm | The upper digital number does not mean accurate measurements to 40,000 ppm. |
| Accuracy from 400–1,000 ppm | ±(50 ppm + 2.5% of reading) for manufacturer applicable operating mode | At 1,000 ppm nominal tolerance is ±75 ppm. |
| Accuracy from 1,001–2,000 ppm | ±(50 ppm + 3% of reading) | Sensitivity and uncertainty depend on concentration band. |
| Accuracy from 2,001–5,000 ppm | ±(40 ppm + 5% of reading) | Do not quote an isolated 2.5% error over 5,000 ppm. |
| Supply, interface | 2.4–5.5 V, I²C, ~15 mA periodic average / 205 mA peak at maker settings | Single-shot reduces average budget but still requires pulse-current capacity. |
| Mechanical / response | 10.1 × 10.1 × 6.5 mm; CO₂ τ63 ~60 seconds | Response time depends on enclosure gas exchange and update interval. |
Selection, calibration and application
SCD41 supports single-shot and low-power sampling modes and has improved banded accuracy compared with SCD40. Evaluate low-power periodic versus single-shot duty against the desired response time: a sporadic sample cannot instantaneously detect occupied-room CO₂ changes. Use RH/T offset configuration, enclosure airflow, air-pressure compensation and proper I²C commands. Fresh-air self-calibration requires periodic exposure to a known near-outdoor baseline; in tightly occupied rooms obtain an independent gas reference before relying on ASC. For active/new designs, the OEM identifies SCD41 as successor to the discontinued SCD42.
Original manufacturer references: SCD41 — extended 5,000 ppm calibrated range and single-shot mode official product data. Latest order code, precise calibrated concentration band and regulatory requirements must be checked before deploying a sensing or safety solution.
AirAlign technical editorial review, 25 October 2026. Not a substitute for current device-specific measurement calibration or certificates.