How to Use SparkFun Triad Spectroscopy Sensor - AS7265x (Qwicc): Examples, Pinouts, and Specs

The SparkFun Triad Spectroscopy Sensor is a sophisticated sensing device that utilizes the AS7265x chipset to provide detailed spectral measurements across a wide range of light wavelengths. This sensor is capable of detecting the intensity of light at 18 different wavelengths, grouped into three sensors: AS72651, AS72652, and AS72653, which cover the ultraviolet, visible, and near-infrared regions, respectively. It is commonly used in color sensing, light analysis, and scientific applications where precise spectral data is required.

• Color matching and calibration
• Light analysis and monitoring
• Agricultural crop health monitoring
• Chemical analysis
• Environmental sensing

• Spectral Range: 410nm - 940nm
• Channels: 18 spectral channels (6 channels per sensor)
• Interface: I2C (via Qwiic connectors)
• Operating Voltage: 3.3V
• Current Consumption: 25mA (typical)
• Field of View: 20 degrees
• Integration Time: 2.8ms to 714ms
• Operating Temperature: -40°C to 85°C

1. Powering the Sensor: Connect the 3V3 and GND pins to a 3.3V power source and ground, respectively.
2. I2C Communication: Connect the SDA and SCL pins to the corresponding I2C data and clock lines on your microcontroller.
3. Interrupts (Optional): The INT pin can be connected to an interrupt-capable GPIO pin on your microcontroller to handle asynchronous events.
4. Reset (Optional): The RST pin can be connected to a GPIO pin to allow software reset of the sensor.

• Ensure that the power supply is stable and within the specified voltage range.
• Use pull-up resistors on the I2C lines if they are not already present on your microcontroller board.
• Avoid exposing the sensor to direct sunlight or high-intensity light sources that could saturate the sensors.
• For accurate measurements, calibrate the sensor periodically using a known light source.

#include <Wire.h>
#include <SparkFun_AS726X.h>

SparkFun_AS726X sensor;

void setup() {
  Wire.begin();
  Serial.begin(115200);
  sensor.begin(Wire, GND, 3V3);
}

void loop() {
  if (sensor.dataAvailable()) {
    sensor.takeMeasurements();
    Serial.print("410nm: ");
    Serial.println(sensor.getViolet());
    // Add additional print statements for other wavelengths as needed
  }
  delay(1000); // Delay between readings
}

• No Data Received: Ensure that the I2C connections are secure and that the correct I2C address is being used.
• Inaccurate Readings: Verify that the sensor is properly calibrated and not exposed to light sources that could cause saturation.
• Intermittent Communication: Check for loose connections and ensure that the pull-up resistors are correctly installed on the I2C lines.

• Double-check wiring and solder joints for any physical connection issues.
• Use I2C scanning code to confirm that the sensor is detected on the I2C bus.
• Reset the sensor using the RST pin if it becomes unresponsive.
• Consult the sensor's datasheet for detailed operational characteristics and troubleshooting steps.

Q: Can the sensor be used with a 5V microcontroller? A: Yes, but level shifting for the I2C lines and a 3.3V power supply for the sensor are required.

Q: How often should the sensor be calibrated? A: Calibration frequency depends on the application's precision requirements. Regular calibration is recommended for critical applications.

Q: Is it possible to connect multiple sensors to the same I2C bus? A: Yes, the AS7265x supports multiple devices on the same I2C bus with different addresses. Ensure that each sensor has a unique address.

Q: What is the maximum I2C speed supported by the sensor? A: The sensor supports standard (100kHz) and fast (400kHz) I2C speeds.