• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 2 answers
  • Subscribers 31 subscribers
  • Views 635 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

TDC1000-TDC7200EVM: a

a a81
Intellectual 390 points
Part Number: TDC1000-TDC7200EVM
Other Parts Discussed in Thread: TDC1000

I want use different frequencies piezoelectrics with TDC1000-TDC7200EVM for liquid concentration application . How can i use them with this EVM and what should i do for using them with this EVM ? Thanks.

  • 0
    TI__Mastermind 31655 points
    Hello,

    Please see the user's guide to find an explanation of the EVM and the GUI. www.ti.com/.../sniu021a.pdf

    To use different frequency sensors you will have to change the transmit frequency setting on the TDC1000 through the GUI. Depending on the frequency of the sensor, you may need to adjust the onboard bandpass filter between PGAOUT and COMPIN on the EVM. The full schematic for the board is included so that you can see where to make these alterations.

    Regards,
  • 0 in reply to Scott Cummins
    Intellectual 390 points
    I wonder what is the best NUM_TX number and what should i change the best configuration? For example ı want to do an application about fluid identification and i change NUM_TX number and so the result change too. I controlled your suggestion document but ı couldnt find the best answer. How can i find the best configuration ? Thanks.
  • 0 in reply to a a81
    TI__Mastermind 31655 points
    Finding the best NUM_TX depends on your transducer and the application. Since you are measuring concentration, and the distance the sound travels is likely fairly short, a smaller number is fine. Even 1 or 2 pulses would likely work just fine in this case in order to reduce the ringdown time of the transducer.

    The systematic way to approach this would be to experiment with increasing NUM_TX numbers until the transmission and ringdown of the transducer interfere with the return echo. Then reduce the number again until it does not interfere. Since this will be a close distance, you will likely not reach the saturation point of the transducer before the transmission starts interfering with the return echo. However, it is still possible, so the way to test for this is to measure the SPL of the transducer output for each NUM_TX setting, and find where the SPL stops increasing with increasing NUM_TX numbers. The proper setting is the one that does not allow transmission interference with the return echo, and does not saturate the transducer. This will allow for the greatest signal to noise ratio and allow you to use a higher threshold for better results.

    Regards,