SMTSOM335BTR

Part: LM135, LM135A, LM235, LM235A, LM335, LM335A — Texas Instruments

Type: Precision Temperature Sensor

Description: Precision, easily-calibrated integrated circuit temperature sensors operating as a 2-terminal zener with a breakdown voltage directly proportional to absolute temperature at 10 mV/°K, featuring less than 1Ω dynamic impedance and operating over a current range of 400 μA to 5 mA.

Operating Conditions:

• Operating current: 400 μA to 5 mA
• Operating temperature: -55 to 150 °C (LM135/LM135A), -40 to 125 °C (LM235/LM235A), -40 to 100 °C (LM335/LM335A)
• Output voltage temperature coefficient: 10 mV/°K

Absolute Maximum Ratings:

• Max forward current: 10 mA
• Max reverse current: 15 mA
• Max storage temperature: -65 to 150 °C

Key Specs:

• Initial Accuracy: 1°C (typ, LM135A/LM235A, T_C = 25°C, I_R = 1 mA)
• Dynamic Impedance: 0.5 Ω (typ, I_R = 1 mA)
• Output Voltage Temperature Coefficient: 10 mV/°C (typ)
• Operating Output Voltage: 2.98 V (typ, T_C = 25°C, I_R = 1 mA)
• Uncalibrated Temperature Error: 0.5 °C (typ, LM135A/LM235A, T_C = 25°C, I_R = 1 mA)
• Non-Linearity: 0.3 °C (typ, I_R = 1 mA)
• Time Constant (Still Air): 80 sec (typ)
• Time Stability: 0.2 °C/khr (typ, T_C = 125°C)

Features:

• Directly Calibrated to the Kelvin Temperature Scale
• 1°C Initial Accuracy Available
• Operates from 400 μA to 5 mA
• Less than 1Ω Dynamic Impedance
• Easily Calibrated
• Wide Operating Temperature Range
• 200°C Overrange
• Low Cost

Applications:

• Power Supplies
• Battery Management
• HVAC
• Appliances

Package:

• TO-46 (3)
• TO-92 (3)
• SOIC (8)

• 1 · Directly Calibrated to the Kelvin Temperature Scale
• 1°C Initial Accuracy Available
• Operates from 400 μ A to 5 mA
• Less than 1Ω Dynamic Impedance
• Easily Calibrated
• Wide Operating Temperature Range
• 200°C Overrange
• Low Cost

• Power Supplies
• Battery Management
• HVAC
• Appliances

TO-46 (NDV) 3 Pins Bottom View

See (1) .

over operating free-air temperature range (unless otherwise noted) (1)(2)(3)(4)

• (3) If Military/Aerospace specified devices are required, please contact the TI Sales Office/Distributors for availability and specifications.

(4) Soldering process must comply with the Reflow Temperature Profile specifications. Refer to http://www.ti.com/packaging.

over operating free-air temperature range (unless otherwise noted)

To insure good sensing accuracy, several precautions must be taken. Like any temperature-sensing device, selfheating can reduce accuracy. The LM135 should be operated at the lowest current suitable for the application. Sufficient current, of course, must be available to drive both the sensor and the calibration pot at the maximum operating temperature as well as any external loads.

If the sensor is used in an ambient where the thermal resistance is constant, self-heating errors can be calibrated out. This is possible if the device is run with a temperature-stable current. Heating will then be proportional to zener voltage and therefore temperature. This makes the self-heating error proportional to absolute temperature the same as scale factor errors.