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TDC1000-TDC7200EVM: Cannot obtain measurement after 95cms

Part Number: TDC1000-TDC7200EVM

Hello, 

    My application involves fixing the transducer to a box and make it float on the top of the water. The approximate tank height is around 2 meters. My GUI is showing measurement till 95 cms and after that there is no measurement obtained. Below is the configuration setting

So, I have three questions

A) Will the setup wont work if the transducer is glued to the box and made to float on water?

B) If it works then what are the settings that I should change so that I can obtain the correct measurement?

C) Should I need to add boost circuit to the EVM to get readings above 95 cms?

  • Hello,

    It seems like the setup is working up to a certain distance for you. However, if you are unable to see past 95cm it could be a problem with the transducer's range, with the box material, or the setup in general. First I would try a box with thinner material. If that does not help, you will likely need to drive the transducer with a greater voltage, and get a transducer capable of accepting a greater voltage. You can reference the TDC1000-GASEVM to see how it has been done previously. The user's guide includes the full schematic: www.ti.com/.../sniu026a.pdf

    Also note that with your current clock frequency you are near the maximum distance that can be measured (about 3.5m round trip, or 1.75m one way). In order to measure up to 2m you will have to change the clock frequency. You can use the internal MSP430 clock set to 2Mhz and change the TX_FREQ_DIV to divide by 2 to work with the 1Mhz transducer. Instructions for how to set up the EVM to use the MSP430 clock are in the user's guide here: www.ti.com/.../sniu021a.pdf

    Regards,

  • Thanks Scott, Will try the above methods!

    Regards,
    Shankar