SNIS118I July   1999  – October 2025 LM50 , LM50HV

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Device Comparison
  6. Pin Configuration and Functions
  7. Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics: LM50 (LM50B and LM50C)
    6. 6.6 Electrical Characteristics: LM50HV
    7. 6.7 Typical Characteristics (LM50B and LM50C)
    8. 6.8 Typical Characteristics (LM50HV)
  8. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 LM50 and LM50HVTransfer Function
    4. 7.4 Device Functional Modes
  9. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Full-Range Centigrade Temperature Sensor
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Capacitive Bypass and Loads
          2. 8.2.1.2.2 LM50HV Self-heating
        3. 8.2.1.3 Application Curve
    3. 8.3 System Examples
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
      2. 8.5.2 Layout Example
      3. 8.5.3 Thermal Considerations
  10. Device and Documentation Support
    1. 9.1 Documentation Support
      1.      Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Layout Guidelines

The LM50 and LM50HV can be applied easily in the same way as other integrated-circuit temperature sensors. The device can be glued or cemented to a surface and the temperature is within about 0.2°C (for power supply up to 10V) of the surface temperature.

This presumes that the ambient air temperature is approximately the same as the surface temperature; if the air temperature are much higher or lower than the surface temperature, the actual temperature of the LM50 and LM50HV dies are at an intermediate temperature between the surface temperature and the air temperature.

To provide good thermal conductivity, the backside of the LM50 and LM50HV dies are directly attached to the GND pin. The lands and traces to the device is part of the printed-circuit board, which is the object whose temperature is being measured. These printed-circuit board lands and traces do not cause the LM50 and LM50HV temperature to deviate from the desired temperature.

Alternatively, the LM50 and LM50HV can be mounted inside a sealed-end metal tube, and can then be dipped into a bath or screwed into a threaded hole in a tank. As with any device, the LM50 and LM50HV and accompanying wiring and circuits must be kept insulated and dry, to avoid leakage and corrosion. This is especially true if the circuit can operate at cold temperatures where condensation can occur. Printed-circuit coatings and varnishes such as HUMISEAL® and epoxy paints or dips are often used to verify that moisture cannot corrode the device or the connections.