Arduino UNO: Temperature Sensor with LM35 🌡️🔌
Level: Beginner – Requires simple code.
🧰 Components Required:
- 1 x Arduino UNO
- 1 x LM35 Temperature Sensor
- Breadboard
- Jumper Wires
🔌 Circuit Connection:
- LM35 Pin 1 (VCC) → connect to Arduino 5V
- LM35 Pin 2 (Vout) → connect to Arduino A0
- LM35 Pin 3 (GND) → connect to Arduino GND
✅ Note: The LM35 outputs analog voltage. Arduino reads it on pin A0 and converts it to a temperature value.
💻 Example Code:
int sensorPin = A0; // LM35 output pin
float sensorValue;
float temperature;
void setup() {
Serial.begin(9600);
}
void loop() {
sensorValue = analogRead(sensorPin);
temperature = (sensorValue * 5.0 * 100.0) / 1024.0;
Serial.print("Temperature: ");
Serial.print(temperature);
Serial.println(" °C");
delay(1000);
}
📘 Explanation:
The LM35 temperature sensor gives an analog voltage that increases by 10mV per °C. Arduino reads this value on pin A0, then converts it into Celsius using a simple formula. The result is displayed in the Serial Monitor, updating every second.