Overview
The LM335AZ/LFT1 is a precision temperature sensor integrated circuit produced by National Semiconductor, now part of Texas Instruments. This device operates as a 2-terminal zener diode, with its breakdown voltage directly proportional to absolute temperature. The LM335AZ is known for its high accuracy, ease of calibration, and wide operating temperature range, making it suitable for various temperature sensing applications.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Operating Temperature Range | -40 | 100 | °C | |
| Forward Current | 0.4 | 1 | 5 | mA |
| Output Voltage Temperature Coefficient | 10 | mV/°C | ||
| Dynamic Impedance | 0.5 | 0.6 | Ω | |
| Storage Temperature | -60 | 150 | °C | |
| Reverse Current | 15 | mA | ||
| Junction-to-Ambient Thermal Resistance (TO-92 Package) | 202 | °C/W |
Key Features
- Directly Calibrated to the Kelvin Temperature Scale: The LM335AZ has a breakdown voltage directly proportional to absolute temperature at 10 mV/°K.
- High Accuracy: Typically less than 1°C error over a 100°C temperature range when calibrated at 25°C.
- Low Dynamic Impedance: Less than 1-Ω dynamic impedance, ensuring minimal impact on performance across the operating current range.
- Easily Calibrated: A simple calibration method using an adjustment terminal allows for higher accuracies.
- Wide Operating Temperature Range: Operates from -40°C to 100°C.
- Low Cost: Offers a cost-effective solution for temperature sensing.
Applications
- Power Supplies: Used in temperature monitoring and control in power supply systems.
- Battery Management: Monitors temperature in battery management systems to ensure optimal performance and safety.
- HVAC Systems: Employed in heating, ventilation, and air conditioning systems for temperature control.
- Appliances: Integrated into various household and industrial appliances for temperature sensing.
Q & A
- What is the operating temperature range of the LM335AZ?
The LM335AZ operates from -40°C to 100°C. - What is the typical forward current for the LM335AZ?
The typical forward current is 1 mA, with a range of 0.4 mA to 5 mA. - How is the output voltage of the LM335AZ related to temperature?
The output voltage is directly proportional to absolute temperature at 10 mV/°K. - What is the dynamic impedance of the LM335AZ?
The dynamic impedance is less than 1 Ω. - Can the LM335AZ be calibrated for higher accuracy?
Yes, it can be easily calibrated using an adjustment terminal. - What are some common applications of the LM335AZ?
Common applications include power supplies, battery management, HVAC systems, and appliances. - What is the storage temperature range for the LM335AZ?
The storage temperature range is from -60°C to 150°C. - What is the junction-to-ambient thermal resistance for the TO-92 package?
The junction-to-ambient thermal resistance is approximately 202 °C/W. - How does the LM335AZ compare to other temperature sensors in terms of accuracy?
The LM335AZ offers high accuracy, typically less than 1°C error over a 100°C temperature range when calibrated at 25°C. - Is the LM335AZ suitable for use in safety-critical applications?
It is important to consult the datasheet and relevant safety guidelines before using the LM335AZ in safety-critical applications.
