LM35D Temperature Sensor (TO-92)
Information
LM35 is the United States NS (National Semiconductor) produced analog temperature sensor, the output voltage is linearly proportional to the Celsius temperature, output at 0 ℃ 0V, the temperature is increased by 1 ℃, the output voltage increases 10mV. Temperature range -55 ~ 150 ℃, an accuracy of 0.75 ℃, precision room temperature up to 0.25 ℃. Common TO-92 package pinout shown in Figure 6, in a temperature range of 2 ℃ ~ 150 ℃ typical application circuit shown below.
Arduino Wiring
The main idea of the program design: Arduino Uno controller via analog input port measurements LM35 output voltage value, and then by the scale factor 10mV / ℃ temperature values calculated. Meanwhile, at the time of 100 ℃, LM35 output voltage is 1000mV, in the internal reference voltage range Arduino Uno controller, so using the internal 1.1V reference voltage.
int Digital_Value=0;
float temp_Value=0;
void setup(){
Serial.begin(9600); //baud rate 9600
//sensing range 0～100℃，output voltage 0～1V，use internal 1.1V reference voltage
analogReference(INTERNAL);
}
void loop(){
Digital_Value=analogRead(A0); //read analog voltage value
temp_Value=(float)Digital_Value/1023*110.00;//change to Celsius value
Serial.print("Temperature for LM35 is: ");
Serial.println(temp_Value,2); //send temperature data
delay(1000); //flash once per second
}