SNOAA67A May   2021  – June 2022 TMP116 , TMP117 , TMP1826 , TMP61 , TMP63 , TMP64


  1.   Abstract
  2.   Trademarks
  3. 1RTD Introduction
    1. 1.1 Common Wiring Configurations
    2. 1.2 RTD Tolerances and Accuracy
    3. 1.3 Error Sources of RTD Systems
      1. 1.3.1 Error Minimization Circuitry
  4. 2RTD Alternatives
    1. 2.1 TMP116 and TMP117
    2. 2.2 TMP1826
    3. 2.3 TMP6x
  5. 3Conclusion
  6. 4References
  7. 5Revision History


Most RTD applications use a current source to excite the RTD element and create a voltage difference. The TMP61 is a linear silicon-based thermistor that has consistent sensitivity across temperature. Using the TMP61 in a current biasing circuit such as Figure 2-6 can offer a method of temperature monitoring to replace the expense and complexity of RTDs. The TMP61 has a positive temperature slope and a temperature measurement range of –40°C to 125°C. The TMP61 can also be used in a voltage biasing circuit, seen in Figure 2-7. The output voltage that corresponds to the measured temperature, VTEMP , is measured across RBIAS.

GUID-FC09F2EA-74DE-408D-9490-0458B7AAD314-low.pngFigure 2-6 TMP61 Current Biasing Circuit
GUID-6E000C27-9B6B-4634-B363-B0900D5A8731-low.pngFigure 2-7 TMP61 Voltage Biasing Circuit
Note: For additional design resources TI provides the Thermistor Design Tool, which offers resistance versus temperature table computation, alternative methods for deriving temperature, and example C-code.