SBOA506 December   2020 OPA2991-Q1 , TLV197-Q1 , TLV2197-Q1 , TLV4197-Q1 , TMP61 , TMP61-Q1 , TMP63 , TMP63-Q1 , TMP64-Q1

 

  1.   Design Goals
  2.   Design Description
  3.   Design Notes
  4.   Design Information
  5.   Design Steps
  6.   Design Simulations
  7.   DC Simulation Results
  8.   Sensor Circuit Accuracy Using a Linear Approximation
  9.   Improving Accuracy of the Sensor Circuit
  10.   Design References
  11.   Design Featured Op Amp
  12.   Design Alternate Op Amp

DC Simulation Results

The desired circuit output voltage response can be simulated in TINA-TI utilizing resistor values calculated in the design section. The following image shows the wide temperature PTC temperature sensor output voltage response simulated using TINA-TI.

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The output voltage curve is not linear and appears almost quadratic. This is due to the TMP61 thermistor response across temperature and the inherent non-linearity of a voltage divider.