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TMP61-Q1: Thermistor Design Tool

TI-CSC
Genius 11230 points
Part Number: TMP61-Q1

Hello E2E Experts,

Good day.

I am using the TMP6131QDYATQ1 PTC Thermistor on a new design and the part's datasheet instructs the user to download the Thermistor Design Tool to obtain Steinhart-Hart parameters, look up tables, etc. 

However, I am not able to enter data such as Vbias, Rbias, and ADC resolution into the worksheet cells because the cells are protected and to unprotect the cells requires a password.

I saw this E2E link that explains why certain parameters are locked on the Excel sheet and I understood the explanation regarding the thermistor design tool.

(+) TMP64-Q1: Could I get the Thermistor Tool sheet password to change the top resistor value away from 47 kΩ? - Sensors forum - Sensors - TI E2E support forums

Is it possible for TI to provide the Steinhart Hart Coefficients for the thermistor if I provide the Vbias (2.5V) and Rbias (10K)?  Here is my circuit configuration:
Regards,
CSC
  • 0
    TI__Guru* 91206 points

    Dear Barry - 

    We highly recommend you move away from using the SHH equation and move to using the polynomial approach, along with leveraging the techniques provided for oversampling, filtering and the ability to do a single point offset correction (that you could never do with an NTC over the entire temp range) as well. You will find that you get certainly as good as and in many cases, better results than you ever will from an NTC. Please see this application note, as it should help you out immensely: https://www.ti.com/lit/an/snia049/snia049.pdf  

    Also, just in case you still choose to use different bias resistor, for the reasons Gordon explained would not be desired to do (from the E2E post you pointed to) - since that post, because this was a request, he did publish an application note on the topic of creating a new 4th order polynomial, because of the design choice or inability to change because of fixed hardware design. https://www.ti.com/lit/an/sboa537/sboa537.pdf