SCD40

Part: SCD4x — Sensirion

Type: Miniature CO2, Humidity, and Temperature Sensor

Description: Miniature CO2 sensor building on photoacoustic NDIR sensing principle, with integrated temperature and humidity sensors, I2C interface, and reflow solderable package. SCD40 offers 400-2'000 ppm CO2 range, while SCD41 offers 400-5'000 ppm with high accuracy and low power modes.

Operating Conditions:

• Supply voltage: 2.4–5.5 V
• Operating temperature: -10 to 60 °C
• Humidity operating conditions: 0–95 %RH (non-condensing)

Absolute Maximum Ratings:

• Max supply voltage: 6.0 V
• Max voltage on pins SDA, SCL, GND: -0.3 V to VDD + 0.3 V
• Max input current on pins SDA, SCL, GND: -280 mA to 100 mA
• Max short term storage temperature: -40 to 70 °C

Key Specs:

• SCD40 CO2 measurement accuracy: ±(50 ppm + 5% of reading) (400 ppm - 2'000 ppm)
• SCD41 CO2 measurement accuracy: ±(50 ppm + 2.5% of reading) (400 ppm - 1'000 ppm)
• CO2 output range: 0 - 40'000 ppm
• Humidity measurement range: 0 %RH - 100 %RH
• Temperature measurement range: -10 °C - 60 °C
• Peak supply current (V DD = 3.3 V): 175 mA (typical), 205 mA (max)
• Average supply current for low power periodic measurement mode (V DD = 3.3 V, 1 measurement every 30 seconds): 3.2 mA (typical), 3.5 mA (max)
• SCL clock frequency: 0 - 400 kHz

Features:

• Photoacoustic NDIR sensor technology PASens®
• Smallest form factor: 10.1 x 10.1 x 6.5 mm³
• Reflow solderable for cost-effective assembly
• Digital I2C interface
• Integrated temperature and humidity sensor

Applications:

• Smart ventilation systems
• Indoor air quality monitors
• Connected devices

Package:

• LGA package (10.1 x 10.1 x 6.5 mm³)

• Photoacoustic NDIR sensor technology PASens®
• Smallest form factor: 10.1 x 10.1 x 6.5 mm 3
• Reflow solderable for cost-effective assembly
• Digital I 2 C interface
• Integrated temperature and humidity sensor

Table 4 : SCD4x electrical specifications

Stress levels beyond those listed in Table 5 may cause permanent damage to the device. Exposure to minimum/maximum rating conditions for extended periods may affect sensor performance and device reliability.

Table 5 : SCD4x operation conditions, lifetime and maximum ratings

6 Supply voltage must be kept constant for stable sensor operation.

7 Valid only for the supply voltage without the load of the sensor.

8 Refers to sustained current.

9 On-demand measurement with freely adjustable interval. See Section 3.10.

10 Accuracy can be reduced at relative humidity levels lower than 10%.

11 Short term storage refers to temporary conditions during e.g., transport.

12 For proper function of the ASC field-calibration algorithm, the SCD4x must be exposed to air with CO2 concentrations of 400 ppm on a weekly basis.

13 Sensor tested over simulated lifetime of >10 years for indoor environment mission profile.

Figure 3 schematically displays the package outline, as well as key nominal dimensions and their tolerances in millimeters. The notched corner of the protection membrane serves as a polarity mark to indicate the location of pin 1. Note that the white protection membrane on top of the sensor must not be removed or tampered with to ensure proper sensor operation. The weight of the sensor is approx. 0.6 g.

Figure 3 : Packaging outline drawing of the SCD4x: (left) top view and (right) side view. Dimensions are given in millimeters.

Figure 3 schematically displays the package outline, as well as key nominal dimensions and their tolerances in millimeters. The notched corner of the protection membrane serves as a polarity mark to indicate the location of pin 1. Note that the white protection membrane on top of the sensor must not be removed or tampered with to ensure proper sensor operation. The weight of the sensor is approx. 0.6 g.