How to Use KY-005: Examples, Pinouts, and Specs

The KY-005 is a digital temperature sensor module that utilizes the DS18B20 sensor to provide accurate and reliable temperature readings. This module is widely used in electronic projects for temperature monitoring and control due to its ease of use and compatibility with microcontrollers like Arduino. The KY-005 supports a wide temperature range and features a digital output, making it suitable for applications such as weather stations, HVAC systems, and industrial temperature monitoring.

• Sensor Type: DS18B20 Digital Temperature Sensor
• Temperature Range: -55°C to +125°C (-67°F to +257°F)
• Accuracy: ±0.5°C (in the range of -10°C to +85°C)
• Operating Voltage: 3.0V to 5.5V
• Output Type: Digital (1-Wire protocol)
• Power Consumption: Low power consumption
• Dimensions: Compact module design for easy integration

The KY-005 module has three pins, as described in the table below:

1. Wiring the KY-005:

   • Connect the GND pin of the KY-005 to the ground (GND) of your microcontroller.
   • Connect the VCC pin to a 3.3V or 5V power supply, depending on your microcontroller's voltage level.
   • Connect the DOUT pin to a digital input pin on your microcontroller.

2. Pull-Up Resistor:

   • The DS18B20 sensor requires a pull-up resistor (typically 4.7kΩ) between the DOUT pin and the VCC pin to ensure proper communication.

3. Programming:

   • Use a microcontroller like Arduino to read temperature data from the KY-005. The module communicates using the 1-Wire protocol, which requires a compatible library.

Below is an example of how to use the KY-005 with an Arduino UNO:

#include <OneWire.h>
#include <DallasTemperature.h>

// Define the pin connected to the KY-005 DOUT pin
#define ONE_WIRE_BUS 2

// Initialize the OneWire and DallasTemperature libraries
OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);

void setup() {
  Serial.begin(9600); // Start serial communication at 9600 baud
  sensors.begin();    // Initialize the DS18B20 sensor
  Serial.println("KY-005 Temperature Sensor Initialized");
}

void loop() {
  sensors.requestTemperatures(); // Request temperature data from the sensor
  float temperature = sensors.getTempCByIndex(0); // Get temperature in Celsius
  
  // Check if the temperature reading is valid
  if (temperature != DEVICE_DISCONNECTED_C) {
    Serial.print("Temperature: ");
    Serial.print(temperature);
    Serial.println(" °C");
  } else {
    Serial.println("Error: Sensor not detected!");
  }
  
  delay(1000); // Wait 1 second before the next reading
}

• Ensure the pull-up resistor is properly connected to the DOUT pin for stable communication.
• Avoid exposing the sensor to temperatures beyond its specified range (-55°C to +125°C).
• Use proper insulation if the sensor is deployed in a humid or wet environment.
• If multiple DS18B20 sensors are used on the same 1-Wire bus, each sensor must have a unique address.

1. No Temperature Reading:

   • Cause: The pull-up resistor is missing or incorrectly connected.
   • Solution: Verify the pull-up resistor (4.7kΩ) is connected between the DOUT and VCC pins.

2. Incorrect Temperature Values:

   • Cause: Poor wiring or loose connections.
   • Solution: Check all connections and ensure the sensor is properly powered.

3. Sensor Not Detected:

   • Cause: The sensor is not properly connected or is damaged.
   • Solution: Verify the wiring and replace the sensor if necessary.

4. Interference on the 1-Wire Bus:

   • Cause: Long wires or noisy environments.
   • Solution: Use shorter wires and shielded cables to reduce interference.

• Q: Can the KY-005 be powered with 3.3V?

  • A: Yes, the KY-005 can operate with a power supply of 3.0V to 5.5V.

• Q: How many sensors can I connect to a single 1-Wire bus?

  • A: You can connect multiple DS18B20 sensors to the same 1-Wire bus, but each sensor must have a unique address.

• Q: Is the KY-005 suitable for outdoor use?

  • A: The sensor itself is not waterproof. If used outdoors, ensure it is properly insulated or use a waterproof version of the DS18B20.

• Q: What is the maximum cable length for the 1-Wire bus?

  • A: The maximum cable length depends on the environment and power supply, but typically it is recommended to keep it under 30 meters for reliable communication.

This concludes the documentation for the KY-005 module.