LM235 - Precision Temperature Sensor | STMicroelectronics | Industrial
MPN: LM235 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.85 | $0.85 |
| 10 | $0.76 | $7.60 |
| 100 | $0.68 | $68.00 |
| 500 | $0.61 | $305.00 |
| 1,000 | $0.55 | $550.00 |
Drop-in alternatives for LM235 — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
LM335
✅ Drop-In📋 Reference alternative (not in catalog)
LM135
✅ Drop-In📋 Reference alternative (not in catalog)
LM235Z
✅ Drop-In📋 Reference alternative (not in catalog)
MCP9700
✅ Drop-In📋 Reference alternative (not in catalog)
TMP36
✅ Drop-In📋 Reference alternative (not in catalog)
LM235 Maximum Ratings & Electrical Characteristics
| Output Type | Analog Voltage |
| Temperature Range | -40°C to +125°C |
| Output Voltage at 25°C | 2.98V (typical) |
| Temperature Coefficient | 10 mV/°C |
| Accuracy at 25°C | ±1°C (typical) |
| Accuracy over Full Range | ±2°C (typical) |
| Supply Voltage Range | 4V to 30V |
| Supply Current | 80 µA (typical) |
| Self-Heating | 0.1°C in still air |
| Output Impedance | 0.1 Ω (typical) |
| Package | TO-92 |
| Mounting Type | Through Hole |
| Operating Temperature | -40°C to +125°C |
| RoHS Status | Compliant |
| Lead-Free | Yes |
LM235 Pin Configuration
| Pin 1 | V+ — Positive supply voltage (4V to 30V) |
| Pin 2 | V- — Ground or negative supply |
| Pin 3 | VOUT — Temperature-dependent output voltage (10 mV/°C) |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this component. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
LM235 is suitable for 6 applications: Industrial Process Control, HVAC Systems, Automotive Engine Temperature Sensing, Battery Temperature Monitoring, Environmental Monitoring, Medical Equipment.
Industrial Process Control
The LM235 is used in industrial process control systems to monitor and regulate temperature in manufacturing processes. Its wide temperature range and accuracy ensure reliable operation in harsh environments. The sensor's linear output simplifies interfacing with ADCs and microcontrollers, enabling precise temperature feedback for control loops. In a typical application, the LM235 is placed in a thermowell or directly in the process medium, and its output is fed to a PLC or microcontroller that adjusts heating or cooling elements. The low self-heating of 0.1°C minimizes measurement errors, ensuring accurate process control. The device's wide supply voltage range of 4V to 30V allows it to be powered from existing industrial power rails without additional regulation.
Recommended
HVAC Systems
The LM235 is widely used in HVAC (Heating, Ventilation, and Air Conditioning) systems for temperature monitoring and control. Its accuracy of ±1°C at 25°C ensures comfortable indoor climates. The sensor's low cost and ease of use make it ideal for mass-produced thermostats and climate control units. In a typical HVAC application, the LM235 is mounted in the return air duct or near the thermostat, and its output is read by a microcontroller that controls the compressor and fan. The device's low self-heating prevents false readings, and its wide supply voltage range allows direct connection to the system's power supply. The linear output simplifies calibration and reduces the need for external components.
Recommended
Automotive Engine Temperature Sensing
The LM235 is used in automotive applications for engine temperature sensing and thermal protection. Its wide temperature range of -40°C to +125°C covers the extremes of engine operation. The sensor's accuracy ensures reliable engine management, preventing overheating and optimizing fuel efficiency. In a typical automotive application, the LM235 is mounted in the engine block or coolant line, and its output is fed to the engine control unit (ECU). The ECU uses the temperature reading to adjust fuel injection, ignition timing, and cooling fan operation. The device's low self-heating and robust construction make it suitable for the harsh automotive environment. The wide supply voltage range allows direct connection to the vehicle's 12V electrical system.
Recommended
Battery Temperature Monitoring
The LM235 is used in battery management systems to monitor battery temperature and prevent thermal runaway. Its low self-heating of 0.1°C ensures accurate temperature readings without affecting the battery. The sensor's small size and low cost make it ideal for integration into battery packs. In a typical application, the LM235 is attached to the battery cell or module, and its output is read by a battery management IC or microcontroller. The system can then adjust charging current or activate cooling mechanisms based on the temperature. The device's wide supply voltage range allows it to be powered from the battery itself, simplifying the design. The linear output makes it easy to calibrate and interface with ADCs.
Recommended
Environmental Monitoring
The LM235 is used in environmental monitoring systems to measure ambient temperature in weather stations, greenhouses, and data centers. Its accuracy and wide temperature range make it suitable for outdoor and indoor monitoring. The sensor's low power consumption of 80 µA is ideal for battery-powered applications. In a typical application, the LM235 is placed in a weatherproof enclosure, and its output is logged by a data logger or transmitted wirelessly. The device's low self-heating ensures accurate readings even in still air. The wide supply voltage range allows it to be powered from solar panels or batteries. The linear output simplifies data processing and reduces the need for complex calibration.
Recommended
Medical Equipment
The LM235 is used in medical equipment for temperature monitoring in incubators, patient monitoring systems, and laboratory equipment. Its accuracy and reliability are critical for patient safety. The sensor's low self-heating and wide temperature range make it suitable for medical applications. In a typical application, the LM235 is used to monitor the temperature of a patient or a medical device, and its output is read by a microcontroller that displays the temperature or triggers alarms. The device's low power consumption is ideal for portable medical devices. The wide supply voltage range allows it to be powered from batteries or medical-grade power supplies. The linear output simplifies calibration and ensures accurate readings.
Recommended
Recommended Products Summary
Engineering reference data for LM235 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LM335 | LM135 | LM235Z | MCP9700 | TMP36 |
|---|---|---|---|---|---|---|
| Package | TO-92 | TO-92 | TO-92 | TO-92 | TO-92 | TO-92 |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics | STMicroelectronics | Microchip Technology | Analog Devices |
| Temperature Range | -40°C to +125°C | -40°C to +100°C | -55°C to +150°C | -40°C to +125°C | -40°C to +125°C | -40°C to +125°C |
| Output Voltage at 25°C | 2.98V | 2.98V | 2.98V | 2.98V | 0.5V | 0.75V |
| Temperature Coefficient | 10 mV/°C | 10 mV/°C | 10 mV/°C | 10 mV/°C | 10 mV/°C | 10 mV/°C |
| Accuracy at 25°C | ±1°C | ±1°C | ±1°C | ±1°C | ±2°C | ±2°C |
| Supply Voltage Range | 4V to 30V | 4V to 30V | 4V to 30V | 4V to 30V | 2.3V to 5.5V | 2.7V to 5.5V |
| Supply Current | 80 µA | 80 µA | 80 µA | 80 µA | 6 µA | 50 µA |
Key Differentiators
- Wider temperature range than LM335 (vs LM335)
- Higher accuracy than MCP9700 (vs MCP9700)
- Wider supply voltage range than TMP36 (vs TMP36)
Design Notes
Place the LM235 away from heat sources on the PCB to minimize measurement errors. Use a ground plane to reduce noise and ensure stable operation. Keep the sensor's leads short to avoid thermal coupling.
The LM235 has a self-heating of 0.1°C in still air. For high-accuracy applications, consider mounting the sensor on a heat sink or in a thermally conductive enclosure to dissipate heat. Avoid placing the sensor near power components that generate heat.
Ensure the supply voltage is within the specified range of 4V to 30V. Exceeding the maximum voltage can damage the device. Also, avoid loading the output with a low-impedance load, as this can affect accuracy. Use a buffer amplifier if driving a low-impedance load.
Compliance Information
RoHS compliant per STMicroelectronics product page. Not AEC-Q100 qualified.
