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TDC1000-C2000EVM: Error 85 occurred at Scan From File (arg 2) in main_tdc1000.vi

Part Number: TDC1000-C2000EVM
Other Parts Discussed in Thread: TDC1000, TUSS4470, PGA460, TUSS4440, TIDA-00322, UCC27531-Q1

Good morning,

I am a first time user of ultrasound and so likely out of my depth but hopefully you can help with a simple application.  I want to measure water level in different objects - glassware for leftovers, acrylic cup, etc...  I bought the TDC1000-c2000evm and SMD10T21R111.  When I downloaded the register file for the transducer I get this error.  Can you please help?  

If you have a base configuration I should be using, please let me know that as well.  I used this too https://webench.ti.com/webench5/TDC/index.html?app=levelHead and reduced the levels for this application.  

My readings are also strange... I hot glued the transducer to a cup and got some readings 38.58357 microseconds.  I did the distance calculation and it wasn't even close to the liquid level.  So I pealed it off and was playing around with holding it to different surfaces and getting some readings and it doesn't really change... I loaded the config.txt file and get new numbers 85.320709 microseconds but it doesn't really change if I release pressure on the side of the glass and move it around, or move it to another object.  I'm such a noob but hope you can point me in the right direction.

Thanks!

Michael

  • Hi Michael,

    If you are only seeking to measure the water level, then I do not recommend the old TDC1000. The TDC1000 is a two channel ultrasonic IC; you only need a single channel ultrasonic IC. 

    Depending on your ultrasonic application use-case, we have specific part recommendations as discussed on the Ultrasonic E2E FAQ: https://e2e.ti.com/support/sensors/f/1023/t/748143 .For level sensing, the PGA460, TUSS4470, or TUSS4440 are my personal recommendations (which I also support directly). This is a reoccurring problem on TI.com at the moment: it seems that all web searches and results regarding level sensing point to the TDC1000, but we are trying to move away from this device. A point of feedback from you that will help prevent other new ultrasonic users from stumbling upon the TDC1000: How did you find and determine to use the TDC1000 for level sensing?

    The register file you are referring to is for the obsoleted TDC1000-TDC7200 EVM. An explanation on the register file compatibility is provided here: https://e2e.ti.com/support/sensors/f/1023/p/878407/3250514#3250514

    Your TDC1000 performance issue may be related to the mounting of the transducer, or a false-positive echo created by the ring-decay of the transducer. Here are some debug recommendations:

    • If the ECHO_QUAL_THLD value is further increased do your results change? The constant 38us result indicates that something from the immediate post-burst phase is triggering the threshold comparator prematurely, which is why you never see the value change based on the water level.
    • Oscilloscope monitor the STOP pulse signals to see if a second stop pulse is triggered at the expected time-of-flight value.

    From the TDC1000 E2E FAQ ( https://e2e.ti.com/support/sensors/f/1023/t/724028?TDC1000-Everything-You-Need-to-Know-for-Ultrasonic-ToF-Liquid-Coupled-Collateral-Tools-Designs-FAQ- ), check out the following for additional guidance on TDC1000 level sensing: How to Select and Mount Transducers in Ultrasonic Sensing for Level Sensing and Fluid ID: http://www.ti.com/lit/an/snaa266a/snaa266a.pdf

     

    View online

  • Good evening Akeem,

    Here is why I bought the TDC1000:

    Case CS0123444 solution proposed (by agent)
    TI Customer Support <ticsc@service-now.com>
    Wed 1/15/2020 2:25 PM
    • Michael Gilkey

    Thank you for contacting TI. We appreciate your business.

    TI has proposed a solution to your case. To view your case, please click this LINK

    Proposed resolution:
    Hi Michael,

    Thank you for contacting Texas Instruments Customer Support. We value your support request.

    I had a great time chatting with you today. From our discussion, to start your project development with TDC1000, you can use the reference design and evaluation module as a guide. Design files, schematics and bill of materials are available for download so that you can accelerate your project development. Please refer on the links below.

    Ultrasonic Sensing for Level and Concentration Measurement Evaluation Module - www.ti.com/.../TDC1000-C2000EVM
    TDC1000-C2000EVM Design File - www.ti.com/.../snar033
    Automotive Ultrasonic Fluid Level/Quality Measurement Reference Design - www.ti.com/.../TIDA-00322

    I hope that you are satisfied with the solution and assistance I have provided you. I will now change the status of this case to "Resolved" and to formally close the case at your end, you may "Accept" the resolution provided. If further assistance is needed, you may reply with this case and I'll be glad to help you more.

    You're always welcome to contact us back to serve you more since your satisfaction is our main priority.

    To also improve our service, you will receive a survey once this request is completed. Please take a moment to provide your honest feedback on your support experience.

    I'm hoping for the best in your project Michael.

    Regards,

    Carlo Cabaccan
    Texas Instruments Customer Support 

    Please acknowledge this email in one of the following two ways:
    1) Click this link to Accept the solution or click this link, Reject to not accept this solution OR
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    Short description: TDC1000 fluid level measurement reference design
    Original details:
     The customer would like to use the TDC1000PW for fluid level measurement and need to know the parts needed to proceed.

    I just ordered this product based on TI's recommendations.  Can I return this product and get the new version you are suggesting?  Please!

    Michael

  • As for the debugging, I'll play with that tomorrow and post how things change with your suggestion.  As for the oscilloscope, is this embedded in the gui or do you mean actually hooking one up?  If the former, how do you bring that up?  If the latter, I don't own one...  

    Thanks again for helping me!

  • 6dB gain, 4 pulses

    38.610803 micros at -220mV

    38.572532 micros at -125mV

    38.628871 micros at -75mV

    38.572511 micros at -50mV

    38.587388 micros at -35mV

  • 21 dB gain, rest same, this is through a glass container ~1/8" thick

    38.841918 micros at -220mV

    38.212796 micros at -35mV

  • I have crazy glued and hot glued per best instructions to a glass container ~5.5" in diameter (square) with water at room temperature.  

    at 21 dB gain and -35mV I get 33.351569 micros

    -125mV I get 33.837232 micros

    -410mV I get a bunch of downward pulses and the average is 32.336641 micros

    -775mV I get 180.977367 micros

    This last one seems to be about right, my calculation comes to 5.28"

  • Akeem, can you please let me know your thoughts.  I also ran into another issue and I believe it is signal drop off due to the amount of liquid I added and the signal isn't being received.  When I go to a depth of 10", I get no signal at all.  Is this a power issue?  Do you have a way to solve this?  Thanks!

    Michael

  • Part Number: TDC1000-C2000EVM

    I believe I have a power issue with a liquid level application going through a metal tank.  At 5", I get transducer signal (@1Mhz) but at 10", I get no signal.  I am using the TDC1000-C2000EVM as suggested by TI customer support (though not as it turns out from technical support).  Is there a way to boost the power?  Thanks,

    Michael

  • Hi Michael,

    You are correct that it is likely the TDC1000's logic level driver is not able to generate sufficient sound pressure level to reach upwards of 10", or it could be that your threshold value is too large. I know you mentioned not having access to an oscilloscope, but an oscilloscope would help to visually debug whether the echo envelope profile of the 10" measurement was too weak or whether the threshold level is too large. I know you currently have the issue of a lower threshold creating a false positive readout at <40us. However, if you were to write a custom program to ignore any time of flight (TOF) measurements that are <40us, then you could report out the second stop pulse, which would be the real TOF in the case where <40us is reported as the first TOF.

    The TDC1000 driver stage can be used in a pre-driver mode to control an external driver block with a larger reference voltage. You can find an example of using the TDC1000 as a pre-driver in the Automotive Ultrasonic Fluid Level/Quality Measurement Reference Design (TIDA-00322) schematic: https://www.ti.com/lit/df/tidrbi0/tidrbi0.pdf . In this schematic, the pre-driver controls a UCC27531-Q1 device to drive the transducer up to 30V.

    The newer TUSS4470 device is able to support a 36V full-bridge driver internally, so you would not need any additional external components.