How to Use XKC-Y26-V: Examples, Pinouts, and Specs

The XKC-Y26-V is a digital temperature and humidity sensor designed for accurate environmental monitoring. Its compact design and dual communication interfaces (I2C and UART) make it versatile and easy to integrate into a wide range of applications. The sensor is ideal for IoT devices, smart home systems, weather stations, and industrial automation projects. With its reliable performance and low power consumption, the XKC-Y26-V is a popular choice for both hobbyists and professionals.

• Temperature Range: -40°C to 85°C
• Humidity Range: 0% to 100% RH
• Temperature Accuracy: ±0.3°C
• Humidity Accuracy: ±2% RH
• Operating Voltage: 3.3V to 5V
• Communication Interfaces: I2C, UART
• Power Consumption: <2mA (active mode)
• Dimensions: 15mm x 10mm x 5mm

The XKC-Y26-V sensor has 4 pins, as described in the table below:

1. Power Supply: Connect the VCC pin to a 3.3V or 5V power source and the GND pin to ground.
2. Communication Interface:
   • For I2C: Connect the SDA pin to the microcontroller's SDA pin and the SCL pin to the microcontroller's SCL pin. Use pull-up resistors (typically 4.7kΩ) on both SDA and SCL lines if not already present.
   • For UART: Connect the Tx pin to the microcontroller's Rx pin and the Rx pin to the microcontroller's Tx pin.
3. Initialization: Configure the microcontroller to use the appropriate communication protocol (I2C or UART) and set the correct baud rate (if using UART).

• Ensure the operating voltage matches the sensor's requirements (3.3V to 5V).
• Avoid placing the sensor in environments with condensation or direct water exposure, as this may affect accuracy.
• For I2C communication, ensure the device address matches the default address of the XKC-Y26-V (typically 0x40 for I2C).

Below is an example of how to use the XKC-Y26-V with an Arduino UNO via I2C:

#include <Wire.h>

// Define the I2C address of the XKC-Y26-V sensor
#define SENSOR_ADDRESS 0x40

void setup() {
  Wire.begin(); // Initialize I2C communication
  Serial.begin(9600); // Initialize serial communication for debugging
  Serial.println("XKC-Y26-V Sensor Initialization...");
}

void loop() {
  Wire.beginTransmission(SENSOR_ADDRESS); // Start communication with the sensor
  Wire.write(0x00); // Command to request temperature and humidity data
  Wire.endTransmission();

  delay(50); // Wait for the sensor to process the request

  Wire.requestFrom(SENSOR_ADDRESS, 4); // Request 4 bytes of data
  if (Wire.available() == 4) {
    uint16_t rawTemp = (Wire.read() << 8) | Wire.read(); // Read temperature
    uint16_t rawHumidity = (Wire.read() << 8) | Wire.read(); // Read humidity

    float temperature = rawTemp / 100.0; // Convert to Celsius
    float humidity = rawHumidity / 100.0; // Convert to percentage

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

    Serial.print("Humidity: ");
    Serial.print(humidity);
    Serial.println(" %");
  } else {
    Serial.println("Error: No data received from sensor.");
  }

  delay(1000); // Wait 1 second before the next reading
}

• Use decoupling capacitors (e.g., 0.1µF) near the VCC pin to reduce noise.
• Keep the sensor away from heat sources or high humidity areas to ensure accurate readings.
• If using UART, ensure the baud rate matches the sensor's default setting (typically 9600 bps).

1. No Data Received:

   • Ensure the wiring is correct and matches the selected communication protocol.
   • Check that the I2C address or UART baud rate is correctly configured in the code.

2. Inaccurate Readings:

   • Verify that the sensor is not exposed to condensation or extreme environmental conditions.
   • Ensure the power supply voltage is stable and within the specified range.

3. Sensor Not Detected:

   • For I2C, check the pull-up resistors on the SDA and SCL lines.
   • For UART, ensure the Tx and Rx lines are not swapped.

Q: Can the XKC-Y26-V operate at 3.3V?
A: Yes, the sensor supports an operating voltage range of 3.3V to 5V.

Q: What is the default I2C address of the XKC-Y26-V?
A: The default I2C address is 0x40.

Q: Can I use the XKC-Y26-V in outdoor environments?
A: While the sensor can operate in a wide temperature and humidity range, it is not waterproof. Use a protective enclosure for outdoor applications.

Q: How often can I read data from the sensor?
A: The sensor can provide readings as frequently as every 1 second, but avoid excessive polling to reduce power consumption.

Q: Does the sensor require calibration?
A: The XKC-Y26-V is factory-calibrated and does not require additional calibration under normal conditions.