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.

ADS1247: IC specifications

Part Number: ADS1247
Dear,
Sorry for the being busy.
I have a question.
Is it impossible to measure liquid temperature with this sensor IC(ADS1247)?
The temperature in the air can be measured correctly, but the temperature when immersed in liquid is incorrect.
Is it such a specification?
Best Regards,
Koji Kuboyama
  • Hello Kuboyama-san,

    Thank you for your question. 

    I would like to fully understand your question. Do you mean that the ADS1247 is submersed in liquid, or just the temperature sensor? 

    As long as the sensor is producing a voltage, the ADS1247 should be able to measure that voltage. 

    Whatever is being immersed in liquid may be shorting out, insulation may be necessary.

    It will be a holiday in the US soon, my next response may be delayed until Monday. 

  • Dear Mr. Smith

    Hello.
    Thank you for answering.


    I will answer your question.
    There are multiple resistors between AIN0 and AIN1 on the AD1247 that are immersed in the liquid.
    The ADS1247 itself is in the air.
    When measured using hot water, it may be negative or lower than the actual temperature(although it is a voltage conversion value).

    Best regards,

    Koji Kuboyama

  • Hello Kuboyama-san,

    I am happy to assist.

    Perhaps the resistors are being shorted out in the liquid. This may then be presented as an incorrect voltage as the resistance of the immersed resistors is shorted out.

    I think it would be best that only non-electrical components be immersed in the liquid. 

    What kind of sensor is this? Can you provide an example picture? 

    Additionally, what are the temperature coefficients for these resistors?

    The resistance may be changing significantly when the resistors are immersed in the liquid, thus leading to inaccuracy. 

  • Hello Kuboyama-san,

    Were you able to resolve the issue? 

  • Dear Mr. Smith

    Hello.
    I am sorry for the late response.

    The target is a MEMS sensor.
    Also, because it is a development product, I cannot send photos.
    In addition, the details of the temperature coefficient are unknown.
    After all, there seems to be some influence in the liquid.
    I am troubled...

    By the way, are there other TI temperature sensors that can measure correctly even in liquids?

    Best regards,

    Koji Kuboyama

  • Hello Kuboyama-san,

    I understand, if it helps I can send you a message offline so that we can communicate in private. 

    Is the MEMS sensor a TI product? If so, you may want to consider posting on the appropriate forum for the sensor. I only work with the ADC devices, so I am not an expert on MEMS sensors. 

    Most of the systems I see use thermocouple or RTD sensors. 

  • Dear Mr. Smith

    Hello.

    The MEMS sensor is a developed product.
    By the way, is this temperature sensor capable of correct measurement in liquid?
    In that case, is it necessary to attach waterproofing to the tip(thermocouple or RTD sensors)?

    Best regards,

    Koji Kuboyama

  • Hi Kuboyama-san,

    Who is the MEMS sensor developed by? Do you have a part number? 

    I do not know what temperature sensor you are referring to. 

    Waterproofing is typically not necessary for thermocouple or RTD sensors. 

    Can you provide pictures of this test to show what exactly is in liquid?