Electronics

Temperature Sensor Linear Module LM35

AED 15.75

1

Description

the LM35 Temperature Sensor Module is a true standout in the world of temperature measurement. Its linear response, exceptional accuracy, low power consumption, and compact size make it the perfect companion for a wide range of applications. Count on the LM35 to deliver consistent and trustworthy temperature data, empowering your projects with the touch of excellence they deserve!

 

Package Includes:

  • 1x LM35 Temperature Sensor Module

Features:

  • Based on the semiconductor LM35 temperature sensor: The module utilizes the LM35, a precision integrated-circuit temperature sensor, known for its accuracy and reliability in measuring temperature.
  • Calibrated directly in ° Celsius (Centigrade): The module comes pre-calibrated, providing temperature readings directly in degrees Celsius without the need for additional adjustments or conversions.
  • Screw holes for easy installation and fixing: The module is designed with convenient screw holes, allowing for hassle-free installation and secure fixing in your projects or applications.
  • Linear + 10 mV/°C Scale Factor: Provides a linear output voltage response with a sensitivity of 10mV per degree Celsius, ensuring accurate temperature measurement.
  • 0.5°C Ensure Accuracy (at +25°C): The module maintains a high level of precision with a maximum deviation of 0.5 degrees Celsius at 25°C, ensuring reliable temperature readings.
  • Low Power Consumption, Less Than 60uA: The module is energy-efficient, consuming minimal power, making it suitable for applications with power constraints.
  • Low Output Impedance, 1mA Current Through Only 0.1Ω: Its low output impedance minimizes voltage drop and ensures stable and accurate temperature measurements.
  • Compact Size: Dimensions of 28mm X wide 12mm X high 10mm, making it space-saving and easy to integrate into various projects.
  • Wide Working Voltage Range: Operates seamlessly with a broad DC voltage range from 4V to 30V, offering flexibility in power supply options.
  • Temperature Measurement Range: Covers a wide temperature range from 0°C to 100°C, suitable for various indoor and outdoor applications.
  • Temperature Measurement Precision: Provides precise temperature readings with an accuracy of ±0.5°C, ensuring reliable data for critical applications.

 

Description:

Discover the LM35 Temperature Sensor Module - a versatile and dependable temperature measuring solution with an array of exceptional features! its Linear + 10 mV/°C Scale Factor ensures temperature measurements with utmost accuracy. The sensor provides a linear output voltage response, boasting a sensitivity of 10mV per degree Celsius, guaranteeing precise and consistent temperature readings.

To further impress, the module boasts a remarkable 0.5°C Ensure Accuracy (at +25°C). With a maximum deviation of only 0.5 degrees Celsius at 25°C, you can rely on this sensor to deliver reliable and trustworthy temperature data, critical for any application. Energy-conscious users will appreciate the Low Power Consumption, consuming less than 60uA. This impressive energy efficiency makes it an ideal choice for projects with power constraints, without compromising on accuracy or performance. The Low Output Impedance of 0.1Ω ensures stable voltage readings with a minimal drop, promoting consistent and accurate temperature measurements. Say goodbye to fluctuations and hello to precision! Size matters and the LM35 Temperature Sensor Module nails it with its Compact Size of 28mm wide, 12mm long, and 10mm high. Its space-saving design simplifies integration into various projects, regardless of space limitations. At its core lies the acclaimed LM35 temperature sensor, known for its accuracy and reliability. This Main Chip guarantees consistent and dependable performance, earning the trust of engineers and hobbyists alike. Whether you're working with a 4V or 30V power supply, the Wide Working Voltage Range ensures seamless operation across a broad DC voltage spectrum, providing flexibility and convenience in power supply options. Embrace the freedom to measure temperatures from 0°C to 100°C with ease. The Temperature Measurement Range is ideal for diverse indoor and outdoor applications, spanning from weather monitoring to industrial processes. For critical applications, accuracy is paramount. Fear not, as the LM35 Temperature Sensor Module provides Temperature Measurement Precision of ±0.5°C, guaranteeing reliable and precise data to drive informed decisions.

 

Principle of Work:

The LM35 temperature sensor operates based on the principle of the voltage drop across a diode-connected transistor. The LM35 contains a temperature-sensitive element that changes its voltage output in proportion to the ambient temperature. The LM35 has three pins - VCC, GND, and Output. When the sensor is powered by a voltage source (typically within the range of 4V to 30V) connected to the VCC pin and grounded through the GND pin, the temperature-sensitive element inside the LM35 reacts to the surrounding temperature. As the temperature increases, the voltage drop between the base and emitter of the transistor changes in a predictable and linear manner.

The Output pin of the LM35 provides an analog voltage output directly proportional to the temperature in degrees Celsius. The voltage output is linear and typically varies at a rate of 10mV per degree Celsius. This means that for every degree Celsius change in temperature, the output voltage changes by 10mV. For example, if the output voltage is 250mV, it indicates a temperature of 25°C. To interface the LM35 with a microcontroller unit (MCU), you need to connect the Output pin of the LM35 to an analog input pin on the MCU. Most MCUs come with built-in analog-to-digital converters (ADCs) that can convert the analog voltage into a digital value, representing the temperature in a more manageable form for processing. Once the MCU reads the analog voltage value from the LM35, you can use the formula:

Temperature (°C) = (ADC_value / ADC_resolution) * Voltage_Step_per_Degree

Where:

  • ADC_value: The digital value obtained from the ADC reading.
  • ADC_resolution: The resolution of the ADC, which represents the number of digital steps.
  • Voltage_Step_per_Degree: The voltage difference corresponding to one degree Celsius (usually 10mV for the LM35).

By utilizing this formula, the MCU can convert the raw ADC value into an accurate temperature reading, allowing you to perform various temperature-based operations and control tasks in your projects or applications. The simplicity, accuracy, and ease of integration make the LM35 a popular choice for temperature sensing with microcontroller units.

 

Pinout of the Board:

  1. VCC: This is the power supply pin for the sensor. It should be connected to a voltage source within the range of 4V to 30V. Make sure to observe the correct polarity while connecting the power supply.
  2. GND: This pin is the ground connection for the sensor. It serves as the reference point for the sensor's operation and completes the circuit. Proper grounding is crucial for accurate temperature measurements.
  3. Analog Out (Vout): The Analog Out pin generates an analog voltage that is directly proportional (linear) to the surrounding temperature. This analog voltage reading should be connected to an Analog-to-Digital Converter (ADC) input on a microcontroller or other digital devices.

 


Applications:

  1. Weather Stations: The module is commonly used in weather monitoring systems to measure outdoor temperatures accurately, providing valuable data for weather forecasting and climate analysis.
  2. Home Automation: In smart home setups, the LM35 sensor is used to control heating, ventilation, and air conditioning (HVAC) systems, ensuring comfortable indoor temperatures and energy efficiency.
  3. Industrial Automation: The module plays a vital role in industrial automation for monitoring temperature in manufacturing processes, storage facilities, and critical equipment, helping to maintain optimal conditions and prevent overheating or damage.
  4. Environmental Monitoring: It is used in environmental monitoring systems to track temperature changes in natural habitats, water bodies, and ecosystems, aiding in ecological research and wildlife conservation efforts.
  5. Greenhouses and Agriculture: In greenhouse environments and agriculture, the LM35 sensor helps regulate temperature and humidity to enhance crop growth and optimize yields.
  6. Home Appliances: It is employed in household appliances such as ovens, refrigerators, and air conditioners to maintain desired temperature settings and ensure safety and efficiency.
  7. Automotive Systems: The module is used in automotive applications for engine temperature monitoring, climate control, and temperature-sensitive systems, contributing to vehicle performance and safety.
  8. Medical Devices: In medical equipment, the LM35 sensor assists in monitoring and controlling temperature-sensitive processes and patient comfort in incubators, blood analyzers, and temperature-controlled chambers.
  9. Energy Management: The module aids in energy management systems by monitoring temperature in power generation and distribution facilities, contributing to improved energy efficiency and reduced operational costs.
  10. Data Centers: In data centers and server rooms, the LM35 sensor is crucial for monitoring server temperatures and ensuring the proper cooling of equipment to prevent overheating and downtime.

 

Circuit:


Let's establish a seamless connection between the LM35 Temperature Sensor Module and the Arduino Uno board for temperature readings. By linking the LM35 Module sensor to the A0 input of the Arduino Uno, we can effortlessly obtain temperature data and showcase it on the serial monitor. Witness the magic unfold as the sensor communicates its accurate measurements, allowing you to monitor the temperature with ease and precision.

 

Library: 

A library is not needed.

 

Code:

This code is a simple Arduino sketch that reads temperature data from an LM35 Temperature Sensor connected to pin A0 of the Arduino board. It then calculates the temperature in both Celsius and Fahrenheit based on the voltage output of the sensor.

#define sensorPin A0

void setup() {
  // Begin serial communication at 9600 baud rate
  Serial.begin(9600);
}

void loop() {
  // Read the voltage from the LM35 Temperature Sensor
  int rawReading = analogRead(sensorPin);

  // Convert the raw ADC reading to voltage (0 to 5V)
  float voltage = (rawReading * 5.0) / 1023.0;

  // Calculate the temperature in Celsius using the LM35's sensitivity of 10mV/°C
  float temperatureC = voltage * 100.0;

  // Calculate the temperature in Fahrenheit
  float temperatureF = (temperatureC * 9.0 / 5.0) + 32.0;

  // Print the temperature readings
  Serial.print("Temperature: ");
  Serial.print(temperatureC, 2); // Print temperature with 2 decimal places for accuracy
  Serial.print("\xC2\xB0C | "); // Show degree symbol for Celsius
  Serial.print(temperatureF, 2); // Print Fahrenheit temperature with 2 decimal places
  Serial.println("\xC2\xB0F"); // Show degree symbol for Fahrenheit

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

  1. It defines the analog pin A0 as sensorPin to which the LM35 Temperature Sensor is connected.
  2. In the setup() function, it initiates serial communication with the computer at a baud rate of 9600. This allows the Arduino to send data to and receive data from the computer via the serial monitor.
  3. In the loop() function, the code continuously runs in a loop, reading temperature data from the LM35 sensor and converting it to both Celsius and Fahrenheit.
  4. It reads the raw analog-to-digital conversion (ADC) value from the sensor using analogRead(sensorPin). The ADC value represents the voltage output of the LM35 sensor.
  5. The raw ADC value is then converted to the corresponding voltage reading (0 to 5V) using the formula voltage = (rawReading * 5.0) / 1023.0, where rawReading is the ADC value.
  6. The temperature in Celsius is calculated based on the LM35's sensitivity of 10mV per degree Celsius. This is achieved with the formula temperatureC = voltage * 100.0.
  7. The temperature in Fahrenheit is calculated by converting the Celsius value using the formula (temperatureC * 9.0 / 5.0) + 32.0.
  8. The temperature readings in both Celsius and Fahrenheit are then printed to the serial monitor. The Celsius value is displayed with two decimal places for accuracy.
  9. After printing the readings, the code adds a delay of 1000 milliseconds (1 second) before taking the next temperature reading. This ensures a time gap between consecutive readings.

 

Technical Details:

  • Linear + 10 mV/°C Scale Factor
  • 0.5°C Ensure accuracy (at +25°C)
  • Low power consumption, less than 60uA
  • Low output impedance, 1mA current through only 0.1Ω
  • Size: 28mm X wide 12mm X high 10mm
  • Main chip: LM35 temperature sensor
  • Working voltage: DC 4-30V
  •  The range of temperature measurement: 0---100 C
  •  The precision of temperature measurement: + 0.5 C
  •  Wide working voltage range: DC4~30V

 

 

Resources:

 Tutorial

Comparisons:

the LM35 is a simple and accurate temperature sensor with analog output, the DS18B20 offers high accuracy and digital communication, and the DHT11 provides both temperature and humidity measurement with an economical price tag. The choice among these sensors depends on specific project requirements, including accuracy, temperature range, power consumption, and budget considerations. Let's compare the LM35 Temperature Sensor to the DS18B20 and the DHT11 temperature sensors based on various aspects:

  1. Sensing Technology:

    • LM35: Solid-state technology, measures temperature based on voltage drop across a diode-connected transistor.
    • DS18B20: Digital sensor using 1-Wire protocol, provides digital temperature data with a unique serial number.
    • DHT11: Digital sensor measuring both temperature and humidity, with single-wire digital interface.
  2. Accuracy:

    • LM35: ±0.5°C at 25°C.
    • DS18B20: ±0.5°C over -10°C to +85°C range.
    • DHT11: ±2°C for temperature.
  3. Temperature Range:

    • LM35: 0°C to 100°C.
    • DS18B20: -55°C to +125°C.
    • DHT11: 0°C to 50°C.
  4. Interface:

    • LM35: Analog voltage output (requires ADC).
    • DS18B20: Digital communication using 1-Wire protocol.
    • DHT11: Single-wire digital interface.
  5. Humidity Measurement:

    • LM35: Temperature-only sensor.
    • DS18B20: Temperature-only sensor.
    • DHT11: Measures temperature and humidity.
  6. Power Consumption:

    • LM35: Low power consumption.
    • DS18B20: Low power consumption.
    • DHT11: Moderate power consumption.