• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Subscribers 32 subscribers
  • Views 165 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

TCAN1042HV: Why final signal of CANH/CANL would produce signal with lower value?

Miles Li1
Intellectual 1640 points
Part Number: TCAN1042HV

Hi team,

Customer is using out TCAN1042HV, and they found that at the end of each message, the signal of CAN bus would be lower at the final bit, which can be seen as below:

And the CANH/L waveform can be seen as below:

Wish to get your reply as soon as possible. Thanks!

  • 0
    TI__Guru 60102 points

    Miles,

    This is interesting, because typically it is the opposite: the bit at the end of the CAN frame has a larger amplitude because multiple devices are sending the ACK bit at once to the bus. 

    • How many nodes are on the bus when these waveforms are captured?
    • And this is at the end of each CAN frame?

    In general, the voltage differential is still high enough that it will be interpreted correctly by the controller through the RXD pin. However, we still need to understand why this is happening.

    Regards,

  • 0 in reply to Eric Hackett
    TI__Intellectual 1640 points

    Hi Eric,

    Reply for your questions are listed as below:

    1. Only two can devices are connected to CAN bus, and one is battery pack and another is connected to computer through TCAN1042HV;

    2. Yes, this is the end of each CAN frame, which can be seen as below：

    Is that a ACK bit? And is there any communication issue caused by this situation? 

    Wish to get your reply by email as soon as possible. Thanks!

  • 0 in reply to Miles Li1
    TI__Guru 60102 points

    This thread is now being handled offline and will be closed.

    Regards,