• State Resolved
  • Locked Locked
  • Replies 5 replies
  • Answers 1 answer
  • Subscribers 32 subscribers
  • Views 843 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TMP103 ACCURACY

Ran Feldman
Intellectual 780 points
Other Parts Discussed in Thread: TMP103, LM20, LM94023, TMP108

Hi,

Our customer would like to use the TMP103. Their application is very small and dense.

Most of the time the operating temperature will be around 100 deg C to 120 deg C.

In the TMP103 Features it says "Accuracy: ±1°C Typ (–10°C to +100°C) "

Looking in the electrical characteristics it seems that when reaching towards 120 deg C there could be a 3 degrees of drift with a 1 deg resolution? is that correct? Figure 5 doesnt take that to account?

The data sheet is speced with 1.8V and our customer will use a 2.5V or 3.3V as V+. Using a higher V+ can improve the error reading from the TMP103?

Please address accuracy and when can one expect a 3 degrees temperature drift from the IC.

Thanks,

Rani

 

  • 0
    TI__Expert 7945 points

    Hello Ran,

    Thank you for posting some interesting questions and thanks for your interest in TMP103. 

    Looking in the electrical characteristics it seems that when reaching towards 120 deg C there could be a 3 degrees of drift with a 1 deg resolution? is that correct? Figure 5 doesnt take that to account?

    3degC is the maximum possible error that you will notice in TMP103. This is the worst case error value and based on the characterization data I noticed that for operating voltages between 2.5V or 3.3V, error will typically be <2degC. 

    Please note that the tabular column on page 3 of data sheet deals with typical and worst case numbers for operating  V+ = +1.4V to +3.6V on the other hand figure 5(and other figures on page 5) of the data sheet show the typical characteristics.

    The data sheet is speced with 1.8V and our customer will use a 2.5V or 3.3V as V+. Using a higher V+ can improve the error reading from the TMP103?

    I checked the data and the part variation with respect to Voltage is not really noticeable.

    Please address accuracy and when can one expect a 3 degrees temperature drift from the IC.

    Just to add to my earlier explain 3degC is the worst case error that may obtained in a lot that takes into account the drift of the part with respect to temperature and with respect to worst case conditions during the parts lifetime. We pick different TMP103 devices from various lots and perform tests and characterization to come up with this number.

    I hope to have clarified your questions.

    Best Regards,

    Abhi Muppiri

    Applications Engineer

    MHR- Sensing Products

    Texas Instruments

    ------------------------------------------------------------------------------------------------------------------------------------------------

    Search for answers, Ask a question, click  Verify  when complete, In the process, Help others, Learn more...

     

     

     

     

  • 0 in reply to Abhishek Muppiri
    Intellectual 780 points

    Hi,

    Thanks for the quick reply. 

    I just wanted also to know regarding the TMP103 Accuracy,  is the total accuracy of max 3C contains the internal A/D accuracy?

    I also want to inquire regarding 2 other devices: The LM20 and LM94023

    What is the worst case accuracy for the  LM20 & LM94023 (working at -40 to 125C).

    Thanks,

    Rani

  • 0 in reply to Ran Feldman
    TI__Intellectual 910 points

    Ran, 

    You may also want to check out the TMP108.   Its just slightly bigger than the TMP103 but offers +/-1.0C (max) across the full -40C to 125C range.  

    -Daniel

  • 0 in reply to Ran Feldman
    TI__Expert 7945 points

    Hello Rani,

    Yes, ADC's accuracy is also included in max 3degC accuracy.

    Our colleague Aaron Heng specializes in LMXX  based temperature sensing portfolio. He will be assisting you shortly.

    Best Regards,

    Abhi

  • 0 in reply to Abhishek Muppiri
    TI__Mastermind 36940 points

    Hi Rani,

    Thank you for your inquiry! The worst case accuracy is listed in Temperature Error row of the EC table. The LM20 and LM94023 are analog output voltage temperature sensors; therefore, it requires ADC to read the voltage. You need to take the ADC’s error into account to know the total worst case accuracy.

    Aaron