Original LM35 Temperature Sensor is an integrated analogue temperature sensor whose electrical output is proportional to Degree Centigrade. LM35 Temperature Sensor does not require any external calibration or trimming to provide typical accuracies. The LM35s low output impedance, a linear output, and precise inherent calibration make interfacing to readout or control circuitry especially easy.
The main advantage of LM35 is that it is linear i.e. 10mv/C which means for every degree rise in temperature the output of LM35 will rise by 10mv. So if the output of LM35 is 220mv/0.22V the temperature will be 22C. So if the room temperature is 32C then the output of LM35 will be 320mv i.e. 0.32V.
As such no extra components required to interface LM35 to ADC as the output of LM35 is linear with 10mv/degree scale. It can be directly interfaced to any 10 or 12 bit ADC. But if you are using an 8-bit ADC likeADC0808orADC0804an amplifier section will be needed if you require to measure 1C change.
LM35 can also be directly connected to Arduino. The output of LM35 temperature can also be given to comparator circuit and can be used for over-temperature indication or by using a simple relay can be used as a temperature controller.

Features of Original LM35 Temperature Sensor:

1. Calibrated directly in Degree Celsius (Centigrade)
2. Linear at 10.0 mV/C scale factor
3. 0.5C accuracyguarantee-able(at a25C)
4. Rated for full -55C to a 150C range
5. Suitable for remote applications
6. Low cost due to wafer-level trimming
7. Operates from 4 to 30 volts
8. Less than 60 mA current drain
9. Low self-heating, 0.08C instil an air
10. Non-linearity only 0.25C typical
11. Low impedance output, 0.1for 1 mA load

Specifications ofOriginal LM35 Temperature Sensor:

1. Local sensor accuracy (Max) (+/- C):0.5
2. Operating temperature range (C): -40 to 110,-55 to 150,0 to 100,0 to 70
3. Supply voltage (Min) (V): 4
4. Supply voltage (Max) (V): 30
5. Supply current (Max) (uA): 14
6. Sensor gain (mV/Deg C): 10
7. Rating:Catalog
8. Features:UL Recognized
9. Interface:AnalogOutput

Package Includes:

1 xOriginal LM35 Temperature Sensor

Code for orignale LM35:

// Define the pin where the LM35 is connected
const int sensorPin = A0; // Analog pin connected to LM35
float voltage; // Variable to store voltage
float temperature; // Variable to store temperature in Celsius

void setup() {
Serial.begin(9600); // Initialize serial communication
}

void loop() {
// Read the analog value from the LM35
int sensorValue = analogRead(sensorPin);

// Convert the analog value to voltage
voltage = sensorValue * (5.0 / 1023.0); // Assuming a 5V system

// Convert voltage to temperature (LM35 gives 10mV per degree Celsius)
temperature = voltage * 100.0;

// Print the results to the Serial Monitor
Serial.print(“Voltage: “);
Serial.print(voltage);
Serial.print(” V | Temperature: “);
Serial.print(temperature);
Serial.println(” C”);

// Wait for a second before the next reading
delay(1000);
}