Project35.Digital Temperature Sensor Module

Description

The KY-028 Digital Temperature Sensor measures temperature changes based on thermistor resistance. This module has both digital and analog outputs, there’s a potentiometer to djust the detection threshold on the digital interface.

Compatible with Arduino, Raspberry Pi, ESP32, and other microcontrollers.

Specification

  • Operating Voltage 3.3V ~ 5.5V

  • Temperature Measurement Range -55°C to 125°C

  • Measurement Accuracy ±0.5°C

  • Board Dimensions 15mm x 36mm

Connect

_images/35_bb.png

Code

int led = 13; // define the LED pin
int digitalPin = 2; // KY-028 digital interface
int analogPin = A0; // KY-028 analog interface
int digitalVal; // digital readings
int analogVal; //analog readings

void setup()
{
pinMode(led, OUTPUT);
pinMode(digitalPin, INPUT);
//pinMode(analogPin, OUTPUT);
Serial.begin(9600);
}

void loop()
{
// Read the digital interface
digitalVal = digitalRead(digitalPin);
if(digitalVal == HIGH) // if temperature threshold reached
{
    digitalWrite(led, HIGH); // turn ON Arduino's LED
}
else
{
    digitalWrite(led, LOW); // turn OFF Arduino's LED
}

// Read the analog interface
analogVal = analogRead(analogPin);
Serial.println(analogVal); // print analog value to serial

delay(100);
}

The analog interface returns a numeric value that depends on the temperature and the potentiometer’s position.

Since the analog output pin is directly connected to the potentiometer it isn’t possible to use the Steinhart-Hart equation to calculate the temperature as we did with the KY-013, we can only use this value to measure relative changes in temperature. Phenomenon ———–

_images/35.jpg