SNIA053 june   2023 TMP61-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Heat Sink Temperature Sensor Monitoring
  5. 2Test Overview
    1. 2.1 Hardware
      1. 2.1.1 Keysight E3631A Power Supply
      2. 2.1.2 Sorensen DCS 40-25E Programmable DC Power Supply
      3. 2.1.3 B&K Precision 8500 DC Electronic Load
      4. 2.1.4 TDS3014B Tektronix Digital Oscilloscope
      5. 2.1.5 Fluke TiS60+ Thermal Imager
      6. 2.1.6 MSP430F5529LP LaunchPad
    2. 2.2 Isolated Gate Driver
    3. 2.3 IGBT Module
    4. 2.4 NTC Ring Lug
    5. 2.5 TMP6 Ring Lug
    6. 2.6 Schematic
  6. 3Test Implementation
    1. 3.1 Data Collected
    2. 3.2 Test Results
  7. 4Design Recommendations
    1. 4.1 Ring Lugs for the TMP6
    2. 4.2 Thermal Epoxy
  8. 5Summary
  9. 6References

1 Heat Sink Temperature Sensor Monitoring

A common method of tracking critical component temperature is to capture the temperature of a heat sink contacting the device of interest, as shown in Figure 1-1. Mechanically, the sensors in these applications can either be attached to the heat sink with epoxy, a clip, or a bolt if the package permits. The equivalent thermal circuit for this method is shown in Figure 1-1, where the RϴJC(IGBT) is the thermal resistance from the junction of the insulated-gate bipolar transistor (IGBT) module to the top of the module package.

GUID-5B56D183-5125-431E-8F3B-0DEF02E2FA0F-low.png Figure 1-1 Equivalent Thermal Circuit for Heat Sink Temperature Sensing

When using this method of temperature monitoring, the measured temperature at the sensor depends on a few key considerations: the thermistor, epoxy, and the mounting stud used for contact. The following sections of this application note explore tradeoffs and considerations when using ring lug thermistors to measure heat sink temperature.