Project35.Digital Temperature Sensor Module
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Description
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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
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- 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
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.. image:: /img/connect/35_bb.png

Code
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.. code-block:: c

    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
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.. image:: /img/phenomenon/35.jpg