LM35 Thermometer With LCD, Fan, Speaker and LED

Let everyone to know the precise temperature inside the house and everywhere in the house. Automatically turn on USB fan, and high temperature sound warning. LED light warning.

Step 1: Step 1: Prepare Your Supplies

Arduino Leonardo

Breadboard

Jumper Wires

USB Cord

LM35 temperature sensor

USB fan

16*2 LCD screen

1 red LED, 1 green LED

1 speaker

30 Wires

Welding torch

Box

Powerbank

Step 2: Step 2: Wiring

Connect supplies voltage to 5V

Connect output to A2

Connect Ground to GND

make sure LM35 face your Leonardo boards.

Connect LCD to Leonardo

Connect fan to board

extend LED wires

Connect speaker

Step 3: Step 3: LCD Screen

GND to GND

VCC to 5V

SDA to SDA

SCL to SCL

Step 4: Steps 4: LED

Extend your LED make it go though the box

Do the same thing to red LED

Step 5: Step 5: Fans

Connect to digital 12 and GND

Step 6: Step 6: Speaker

Step 7: Step 3: Coding

#include <Wire.h> 
#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd_I2C_27(0x27,16,2); // set the LCD address for a 16 chars and 2 line display

void setup(){  // put your setup code here, to run once:
  lcd_I2C_27.init (); // initialize the lcd
  lcd_I2C_27.backlight();
  pinMode( 7 , OUTPUT);
  pinMode( 8 , OUTPUT);
  pinMode( 12 , OUTPUT);
}

void loop()
{
  int sensorValue = analogRead(A0);
  float millivolts = (sensorValue / 1024.0) * 5000; 
  float celsius = millivolts / 10;
  lcd_I2C_27.setCursor(2, 0);
  lcd_I2C_27.print( "Temperature" );
  lcd_I2C_27.setCursor(4, 1);
  lcd_I2C_27.print(celsius);
  lcd_I2C_27.setCursor(10, 1);
  lcd_I2C_27.print("C");
 
  if ( celsius >= 28 ) {
    digitalWrite( 8 , HIGH );
    digitalWrite( 7 , LOW );
    digitalWrite( 12 , HIGH );
    tone(11, 1000, 100);
  }
  else
  {
    digitalWrite( 7 , HIGH );
    digitalWrite( 8 , LOW );
    digitalWrite( 12 , LOW );
  }
  delay(50);
}