SBOS921F December   2018  – November 2023 TMP61

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
    6. 6.6 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 TMP61 R-T table
      2. 7.3.2 Linear Resistance Curve
      3. 7.3.3 Positive Temperature Coefficient (PTC)
      4. 7.3.4 Built-In Fail Safe
    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 Thermistor Biasing Circuits
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Thermal Protection With Comparator
          2. 8.2.1.2.2 Thermal Foldback
        3. 8.2.1.3 Application Curve
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Receiving Notification of Documentation Updates
    2. 9.2 Support Resources
    3. 9.3 Trademarks
    4. 9.4 Glossary
    5. 9.5 Electrostatic Discharge Caution
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information
8.2.1.2.1 Thermal Protection With Comparator

Use the TMP61 device along with a voltage reference, and a comparator to program the thermal protection. As shown in Figure 8-10, the output of the comparator remains low until the voltage of the thermistor divider, with RBIAS and RTMP61, rises above the threshold voltage set by R1 and R2. When the output goes high, the comparator signals an overtemperature warning signal. The engineer can also program the hysteresis to prevent the output from continuously toggling around the temperature threshold when the output returns low. Either a comparator with built-in hysteresis or feedback resistors may be used.

GUID-5EF3F599-04BF-491B-975E-3A3446066E2F-low.jpgFigure 8-10 Temperature Switch Using TMP61 Voltage Divider and a Comparator