Design with Temperature Sensor (LM35) in Cirkit DesignerThe LM35 is a precision temperature sensor that provides an output voltage proportional to the temperature in degrees Celsius. Unlike many other temperature sensors, the LM35 does not require any external calibration or trimming to provide accurate readings. It is highly reliable, easy to use, and offers a linear output, making it a popular choice for temperature measurement and control applications.
This circuit is designed to measure temperature using an LM35 temperature sensor and display the readings in degrees Celsius. The sensor's output voltage is read by an Arduino UNO's analog input, which then converts the voltage to a temperature value. The Arduino is programmed to serially output the temperature data, which can be monitored in real-time.
Open Project in Cirkit Designer
This circuit is designed to measure temperature using an LM35 temperature sensor interfaced with an Arduino UNO microcontroller. The sensor's output voltage, which is proportional to the temperature, is read by the Arduino's analog input A0. The embedded code on the Arduino processes this signal to calculate and output the temperature in both Celsius and Fahrenheit to the serial monitor.
Open Project in Cirkit Designer
This circuit is designed to measure temperature using an LM35 temperature sensor interfaced with an Arduino UNO microcontroller. The sensor's output voltage, which is proportional to the temperature, is fed into the Arduino's analog input A1 for processing. The Arduino is powered by 5V and shares a common ground with the sensor, setting up the basic framework for temperature data acquisition.
Open Project in Cirkit Designer
This circuit uses an Arduino UNO to read temperature data from an LM35 temperature sensor. The sensor's output is connected to the Arduino's analog input pin A0, and the Arduino processes this data to calculate and display the temperature in Celsius on the Serial Monitor.
Open Project in Cirkit DesignerThe LM35 is designed to operate over a wide range of temperatures and provides accurate readings with minimal power consumption. Below are the key technical details:
| Parameter | Value |
|---|---|
| Supply Voltage (Vcc) | 4V to 30V |
| Output Voltage Range | 0V to 1.5V (for 0°C to 150°C) |
| Temperature Range | -55°C to +150°C |
| Accuracy | ±0.5°C (at 25°C) |
| Output Sensitivity | 10mV/°C |
| Current Consumption | 60 µA (typical) |
| Load Impedance | ≥ 10 kΩ |
The LM35 is typically available in a 3-pin TO-92 package. Below is the pinout and description:
| Pin Number | Pin Name | Description |
|---|---|---|
| 1 | Vcc | Positive power supply (4V to 30V) |
| 2 | Vout | Analog output voltage proportional to temperature |
| 3 | GND | Ground (0V reference) |
The LM35 is straightforward to use in a circuit. Follow the steps below to integrate it into your project:
Below is an example of how to use the LM35 with an Arduino UNO to read and display temperature:
// LM35 Temperature Sensor Example with Arduino UNO
// Reads temperature in Celsius and displays it on the Serial Monitor
const int sensorPin = A0; // LM35 output connected to analog pin A0
float temperature; // Variable to store the temperature value
void setup() {
Serial.begin(9600); // Initialize serial communication at 9600 baud
}
void loop() {
int sensorValue = analogRead(sensorPin); // Read the analog value from LM35
// Convert the analog value to voltage (assuming 5V reference voltage)
float voltage = sensorValue * (5.0 / 1023.0);
// Convert voltage to temperature in Celsius (10mV per degree Celsius)
temperature = voltage * 100.0;
// Print the temperature to the Serial Monitor
Serial.print("Temperature: ");
Serial.print(temperature);
Serial.println(" °C");
delay(1000); // Wait for 1 second before the next reading
}
Incorrect Temperature Readings
No Output or Constant Zero Voltage
Fluctuating Readings
Q1: Can the LM35 measure negative temperatures?
Yes, the LM35 can measure temperatures below 0°C. However, the output voltage will be negative, so additional circuitry or software adjustments are required to interpret the readings.
Q2: Can I use the LM35 with a 3.3V microcontroller?
Yes, the LM35 works with a 3.3V supply. However, the output voltage range will be limited, and you may need to adjust the analog-to-digital conversion calculations accordingly.
Q3: How do I extend the sensor's range beyond 150°C?
The LM35 is limited to 150°C. For higher temperature ranges, consider using a different sensor, such as the LM135 or thermocouples.
Q4: Is the LM35 waterproof?
No, the LM35 is not waterproof. For outdoor or liquid temperature measurements, use a waterproof housing or a sensor designed for such applications.
By following this documentation, you can effectively integrate the LM35 temperature sensor into your projects and troubleshoot common issues with ease.