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.

  • TI Thinks Resolved

Electrical Conductivity and PH design circuit

Dear All

Is there any reference design or application note on how to create the circuit for a EC and PH probe circuit for liquid substances?

Or if someone can point me in the right direction. 

Thanks

Regards

DJ

  • Hello Dharmesh,

    LMP91200 is an Integrated analog front end for pH Sensing Applications and we have a reference design that uses this part, TIDA-00561, which you can find in the following link:

    Best Regards,
    Victor S.
    Systems Engineer - Test & Measurement Solutions 
     Check my Recommended TI Resources

  • In reply to Victor Salomon:

    Thank You
    How would i develop a electrical conductivity meter with this IC or any other?
  • In reply to Dharmesh Joshi:

    Dharmesh,

    There is a couple of approaches used in Electrical Conductivity depending on your application. If you are considering Inductive Sensing check out the products available and for any Inductive Sensing specific questions please go to the Inductive Sensing Forum.

    If you are using electrode conductivity sensors you will need to work on your signal conditioning, refer to the following E2E Post for reference:

    Best Regards,
    Victor S.
    Systems Engineer - Test & Measurement Solutions 
     Check my Recommended TI Resources

  • In reply to Victor Salomon:

    Dear Victor
    Thank You for your reply
    Yes i would like to use this for testing in solution as well as soil samples. Could this be achieved with inductive sensing?

    I will also read that post that you recommended.

    Thank You
  • In reply to Victor Salomon:

    Dear Victor

    I had a look


    Can you please explain what you mean by signal conditioning? Would this mean by signal output such as sine wave?

    I am thinking using the PWM output of my microcontroller. I am not sure how this would be incorporated as an AC signal, with 3.3V

    As suggested to use an transimpedance amplifier, which is first schematic, but is the second schematic is total different design?

    Where would probes connect?

    Would you have any document on this?
  • In reply to Dharmesh Joshi:

    Dharmesh,

    I hope I can address some of your questions for for more specifics I would recommend posting on the forum of the technology you are considering (e.g. Inductive Sensing Forum or Precision Amplifiers Forum).

    Dharmesh Joshi
    Can you please explain what you mean by signal conditioning? Would this mean by signal output such as sine wave?

    What I mean is the circuit you would design to condition the signal to be appropriate for the input of our ADC, such are the two examples on the post I shared.

    Dharmesh Joshi
    I am thinking using the PWM output of my microcontroller. I am not sure how this would be incorporated as an AC signal, with 3.3V... As suggested to use an transimpedance amplifier, which is first schematic, but is the second schematic is total different design?

    I am not too familiar with Conductivity Probes, but from I can gather you measure the current given the change in conductivity, for any further questions on this post on the Precision Amplifiers Forum.

    Dharmesh Joshi
    Where would probes connect? Would you have any document on this?

    We do have application specific documentation (see: ti.com/applications), however, we do not have a specific page for 'Conductivity Probes', but we do have a more general page for 'Process Analytics'.

    Best Regards,
    Victor S.
    Systems Engineer - Test & Measurement Solutions 
     Check my Recommended TI Resources

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.