#define LM35 A0
#define LED 3
int data;
float vo, temp;
void setup()
{
  Serial.begin(9600);
  pinMode(LED, OUTPUT);
  analogReference(INTERNAL);
}

void loop()
{
  temp = 0;
  for (int i = 1; i < 10; i++)
  {
    data = analogRead(LM35);
    vo = (data / 1023.0) * 1.1;
    temp += vo * 100;
    delay(200);
  }
  temp /= 10;
  Serial.print("Data = ");
  Serial.print(data);
  Serial.print(", Vin= ");
  Serial.print(vo);
  Serial.print("[V]");
  Serial.print(",Temp = ");
  Serial.print(temp);
  Serial.println("[C]");
  if (temp > 25)
    digitalWrite(LED, 1);
  else
    digitalWrite(LED, 0);
  delay(1000);
}