LM 35 Temperature Sensor

The LM35 Temperature Sensor is a precision integrated-circuit temperature sensor with an output voltage linearly proportional to Celsius temperature. It requires no external calibration and provides accurate temperature readings for monitoring and control applications.

Key Features

• Linear +10mV/°C scale factor for easy temperature calculation
• Rated for full -55°C to +150°C range
• 0.5°C accuracy at room temperature
• Low self-heating for accurate readings
• Low impedance output for easy interfacing
• 4V to 30V operating voltage
• No external calibration required

Technical Specifications

Applications

• Room temperature monitoring and HVAC control
• Industrial process monitoring
• Engine temperature sensing
• Environmental data logging
• Greenhouse climate control
• Educational electronics projects

Important Notes

• Output is analog voltage – requires ADC pin on microcontroller
• For temperatures below 0°C, negative voltage handling needed
• TO-92 package is fragile – avoid bending leads excessively
• Thermal mass is low – responds quickly to air temperature changes
• Multiple LM35s can share one ADC via multiplexer if pins limited