Overview
The LM335AMX is a precision temperature sensor produced by Texas Instruments. It operates as a 2-terminal zener diode, with its breakdown voltage directly proportional to absolute temperature at a rate of 10 mV/°K. This device is part of the LMx35 series, known for their ease of calibration and high accuracy over a wide temperature range.
The LM335AMX is specifically designed to operate from -40°C to 100°C, making it suitable for various temperature sensing applications. It has a low dynamic impedance of less than 1 Ω and can operate with a current range of 400 μA to 5 mA, ensuring consistent performance across different conditions.
Key Specifications
| Parameter | Test Conditions | Unit | Min | Max | |
|---|---|---|---|---|---|
| Operating Temperature Range | Continuous | °C | -40 | - | 100 |
| Forward Current | - | mA | 0.4 | 1 | 5 |
| Operating Output Voltage | TC = 25°C, IR = 1 mA | V | 2.95 | 2.98 | 3.01 |
| Uncalibrated Temperature Error | TC = 25°C, IR = 1 mA | °C | 1 | 3 | 6 |
| Dynamic Impedance | IR = 1 mA | Ω | 0.5 | 0.6 | - |
| Output Voltage Temperature Coefficient | - | mV/°C | 10 | - | - |
| Junction-to-Ambient Thermal Resistance | - | °C/W | 165 | - | - |
Key Features
- Directly Calibrated to Kelvin Temperature Scale: The LM335AMX has a breakdown voltage directly proportional to absolute temperature at 10 mV/°K.
- High Accuracy: When calibrated at 25°C, the device has a typical error of less than 1°C over a 100°C temperature range.
- Low Dynamic Impedance: Less than 1 Ω, ensuring minimal impact on the circuit.
- Wide Operating Current Range: Operates from 400 μA to 5 mA with consistent performance.
- Easily Calibrated: A single-point calibration method using the ADJ pin corrects for inaccuracies over the full temperature range.
- Linear Output: Unlike other sensors, the LM335AMX has a linear output, making it easier to interface with readout or control circuitry.
- Low Cost: An economical solution for precision temperature sensing.
Applications
- Power Supplies: For temperature monitoring and control in power supply units.
- Battery Management: To monitor battery temperature in various battery management systems.
- HVAC Systems: For temperature sensing in heating, ventilation, and air conditioning systems.
- Appliances: Used in household and industrial appliances for temperature monitoring and control.
- General Temperature Sensing: Suitable for any application requiring precise temperature measurement over a -40°C to 100°C range.
Q & A
- What is the operating temperature range of the LM335AMX?
The LM335AMX operates from -40°C to 100°C.
- How does the LM335AMX calibrate for temperature?
The device can be calibrated using a single-point calibration method via the ADJ pin.
- What is the dynamic impedance of the LM335AMX?
The dynamic impedance is less than 1 Ω.
- What is the output voltage temperature coefficient of the LM335AMX?
The output voltage temperature coefficient is 10 mV/°C.
- What are the typical applications of the LM335AMX?
It is used in power supplies, battery management, HVAC systems, appliances, and general temperature sensing applications.
- What is the junction-to-ambient thermal resistance of the LM335AMX?
The junction-to-ambient thermal resistance is 165 °C/W.
- How does the current range affect the performance of the LM335AMX?
The device operates from 400 μA to 5 mA with virtually no change in performance.
- What is the typical error of the LM335AMX after calibration?
After calibration at 25°C, the typical error is less than 1°C over a 100°C temperature range.
- How does the LM335AMX compare to other temperature sensors in terms of output linearity?
The LM335AMX has a linear output, which is an advantage over other sensors that may have non-linear outputs.
- What are the package options for the LM335AMX?
The LM335AMX is available in an SOIC (D) package.
