MSP430FR6043: Information of Application note about Ultrasonic Sensing

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Part Number: MSP430FR6043
Other Parts Discussed in Thread: TIDM-1019

I have two questions about the application note.

1.Liquid Level Sensing

https://www.ti.com/lit/an/slaa951a/slaa951a.pdf

From the application note 2 Test result, it is stated that it can detect 50 ns absolute time, while Figure 2-2 only detects 5us time.

Do you have any information if 50ns detection is feasible?

 

2.Oxygen Concentration Sensing

https://www.ti.com/lit/an/slaa976/slaa976.pdf

In the application note 1 Introduction, there is a description of "measurement periods of less than 10 ms".

Does this statement mean "UPS to UPS1 GAP =10 ms"?

If so, please tell me the specific setup procedure.

Thanks,

Koki

  • Hi Koki,

    Please see answers below:

    1. 50ns is based on the standard deviation in measurements. (not the absolute time of flight)

    2. In order to achieve this rate, the sleep statement needs to be disabled in the while loop of the code.

    BR,

    Leo

  • Hi, LEO

    1. 50ns is based on the standard deviation in measurements. (not the absolute time of flight)

    In the documentation, I find the following:

    "The test setup described in this document can sense changes in the absolute time of flight of less than 50 ns."

    Is this correct in the recognition that it can detect changes in absTOF of 50ns or less?

    From the "Liquid Level Sensing Test Results" in Figure 2-2., I think it is difficult to recognize the change of 50ns.

     

    statement needs to be disabled in the while loop of the code.

    Please tell me the specific procedure in USS Lib.

     

    Thanks,

    Koki

  • Hi Koki,

    I see your point now.

    1. The screen capture shows 500ns of StD- not 50ns of StD because the level transition is included in the GUI calculation(the GUI is computing the StD). Yes, it's possible to achieve the 50ns resolution. (I'd be happy to help you replicate this test setup - please email me so that I can support your evaluation.)

    2.         USSLibGUIApp_Delay();  

    BR,

    Leo

  • Hi, LEO

    1. The screen capture shows 500ns of StD- not 50ns of StD because the level transition is included in the GUI calculation(the GUI is computing the StD).
    The standard deviation surrounded by a red frame is about 500ns in this demo, but it is possible to achieve a standard deviation of 50ns.
    Is it okay to understand that?

     

    2. Please tell me where to look in the results of the application note to see that the measurement cycle is less than 10msec.

     Or could you please confirm how many msec cycles you were able to achieve in the application note result?

    Thanks,

  • Hi Leo

    Do you have any update?

    Thanks,

    Koki

  • Hi Koki,

    You're understanding is correct for 1. above.

    You can find the timing diagram for calculation of both absolute time of flight and delta time of flight in TIDM-1019 Figure 26:

    https://www.ti.com/lit/ug/tidudn0/tidudn0.pdf

    the upstream/downstream gap can be reduced to a millisecond and by disabling the sleep as mentioned above, the measurement rate can be reduced to less than 10ms.

    BR,
    Leo