• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 79 subscribers
  • Views 277 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.

EVM430-FR6043: Electrical Coupling Issue

Luke
Expert 4000 points
Part Number: EVM430-FR6043


Tool/software:

Hi team, 

My customer is using the EVM430-FR6043 eval kit and seeing some electrical coupling issues (J5&J6) and needs some help reaching a solution. 

They are working on developing an ultrasonic airflow sensor and have the following questions:

  1. I’m seeing some noise on the Rx line that’s lining up with the Tx signal. Is this normal? Is there a suggested fix for it?
  2. Can I get the PCBDoc for this board as either a .brd or an ASCII PCBDoc? We use allegro so I’m unable to open the binary PCBDoc provided.
  3. Is there an advantage to multiplexing one set of Rx/Tx channels instead of one pair per transducer?
  4. Does TI have any resources on mounting the ultrasonic transducers? I’ve been experimenting with them a lot and would really appreciate a dependable knowledge source

Best,

Luke

  • 0
    TI__Genius 16030 points

    Hi Luke,

    1) There is bound to be some coupling between TX and RX on the device, are you actually seeing some problem with the final measurements calculated by the device? If yes, some helpful info would be a) Where exactly are you probing to see this, b) images of the scope shots visualizing the noise, c) What errors the device is reporting or what incorrect values you are seeing.

    2) You can find design documents for this device on the TIDM-02003 page. Unfortunately these are the only revisions of the PCB document that we have so if you are unable to open this version currently we need to find a workaround using the design documents on the TI Design page.

    3) Multiplexing the one channel makes it much easier to match impedance on the RX and TX sides. Using separate hardware for TX and RX means that we must very carefully match the impedances on each side in order to achieve the highest signal strength and in turn the most reliable time of flight calculations.

    4) We have some basic info, if you had specific questions I may be able to help here. In terms of existing resource I believe we are limited to our app note on clamp on flow metering.

**Attention** This is a public forum