SNIS118I July   1999  – October 2025 LM50 , LM50HV

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison
  6. 5 Pin Configuration and Functions
  7. 6 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. 7 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. 8 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. 9 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

8.3 System Examples

Figure 8-10 to Figure 8-12 show application circuit examples using the LM50 and LM50HV devices. Figure 8-10 shows a Centigrade Thermostat or Fan Controller configuration based on Schmitt trigger circuit. LM50 and LM50HV devices can detect the ambient temperature in which the upper and lower temperature thresholds can be adjusted by R1, R2 and R3 resistors.

LM50 LM50HV Centigrade Thermostat or Fan ControllerFigure 8-10 Centigrade Thermostat or Fan Controller

The LM50/LM50HV output voltage can be digitized by using ADC and voltage reference (LM4041) as shown in Figure 8-11.

LM50 LM50HV Temperature To Digital Converter (Serial Output)
125°C full scale
Figure 8-11 Temperature To Digital Converter (Serial Output)

The temperature detected by LM50/LM50HV can be converted to frequency by using LM131. The desired frequency range can be adjusted by selecting different values for resistors and capacitors while Figure 8-12 shows an example for converting -40°C to 125°C temperature range to 100Hz to 1.75kHz frequency range.

Customers must fully validate and test any circuit before implementing a design based on an example in this section. Unless otherwise noted, the design procedures in Full-Range Centigrade Temperature Sensor are applicable.

LM50 LM50HV LM50 and LM50HV With Voltage-To-Frequency Converter and Isolated Output
–40°C to 125°C; 100Hz to 1750Hz
Figure 8-12 LM50 and LM50HV With Voltage-To-Frequency Converter and Isolated Output