How to Use SCD30: Examples, Pinouts, and Specs

The SCD30, manufactured by Sensirion, is a high-precision digital sensor designed for measuring carbon dioxide (CO2), temperature, and humidity. It employs non-dispersive infrared (NDIR) technology for CO2 detection, ensuring accurate and reliable measurements. The SCD30 is widely used in applications such as indoor air quality monitoring, HVAC systems, greenhouses, and smart home devices. Its compact design and integrated temperature and humidity sensors make it a versatile solution for environmental sensing.

The SCD30 offers robust performance and precise measurements. Below are its key technical details:

The SCD30 has a 6-pin interface for power and communication. Below is the pinout description:

The SCD30 can be easily integrated into a circuit for CO2, temperature, and humidity sensing. Below are the steps and best practices for using the sensor:

1. Power Supply: Connect the VDD pin to a 3.3V or 5V power source and the GND pin to ground.
2. I2C Communication:
   • Connect the SDA pin to the I2C data line of your microcontroller.
   • Connect the SCL pin to the I2C clock line of your microcontroller.
   • Use pull-up resistors (typically 4.7 kΩ) on the SDA and SCL lines if not already present.
3. UART Communication (Optional):
   • Connect the RX pin to the TX pin of your microcontroller.
   • Connect the TX pin to the RX pin of your microcontroller.

Below is an example of how to use the SCD30 with an Arduino UNO via I2C:

#include <Wire.h>
#include <SparkFun_SCD30_Arduino_Library.h> // Include the SCD30 library

SCD30 airSensor; // Create an SCD30 object

void setup() {
  Serial.begin(9600); // Initialize serial communication
  Wire.begin();       // Initialize I2C communication

  if (airSensor.begin() == false) {
    Serial.println("SCD30 not detected. Check wiring and try again.");
    while (1); // Halt execution if the sensor is not detected
  }
}

void loop() {
  if (airSensor.dataAvailable()) {
    // Read and print CO2, temperature, and humidity values
    Serial.print("CO2 (ppm): ");
    Serial.println(airSensor.getCO2());

    Serial.print("Temperature (°C): ");
    Serial.println(airSensor.getTemperature());

    Serial.print("Humidity (%): ");
    Serial.println(airSensor.getHumidity());

    Serial.println(); // Print a blank line for readability
  } else {
    Serial.println("No data available. Waiting...");
  }

  delay(2000); // Wait 2 seconds before the next reading
}

• Ensure the sensor is placed in an environment with good airflow for accurate readings.
• Avoid exposing the sensor to high humidity or condensation for prolonged periods.
• Calibrate the sensor periodically for optimal performance, especially in environments with varying CO2 levels.
• Use appropriate pull-up resistors for I2C communication to ensure signal integrity.

1. Sensor Not Detected:

   • Verify the wiring connections, especially the SDA and SCL lines.
   • Ensure the correct I2C address (default: 0x61) is being used in your code.
   • Check the power supply voltage (3.3V to 5.5V).

2. Inaccurate Readings:

   • Allow the sensor to warm up for at least 15 minutes after powering on.
   • Ensure the sensor is not exposed to direct sunlight or heat sources.
   • Perform a manual calibration if readings deviate significantly.

3. No Data Available:

   • Confirm that the dataAvailable() function is being called correctly in the code.
   • Check for proper pull-up resistors on the I2C lines.

Q: Can the SCD30 measure CO2 levels below 400 ppm?
A: No, the SCD30 has a minimum CO2 measurement range of 400 ppm.

Q: How often should I calibrate the SCD30?
A: Calibration frequency depends on the application. For most indoor environments, calibration every 6-12 months is sufficient.

Q: Can I use the SCD30 with a 3.3V microcontroller?
A: Yes, the SCD30 is compatible with both 3.3V and 5V systems.

Q: What is the default I2C address of the SCD30?
A: The default I2C address is 0x61.

By following this documentation, you can effectively integrate and use the SCD30 sensor in your projects.