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.

About the action of SN75976A

Guru 19475 points

What kind of operation does the receiver input pin of SN75976 become at the time of OPEN in both?
(Is it floating and become Non-reccomended?)

Thank you for your consideration.

  • Hi Satoshi,

    To make sure I understand your question correctly. Are you asking the following: What will the output of the receiver be if the differential pair is left floating and the receiver is enabled?

    For this case, when both pins of the bus are left floating, there will be no differential voltage on the input of the receiver. Since the receiver has a positive threshold of 200mV and a negative threshold of -200mV (page 8 of the datasheet), you will then be in the undetermined voltage area of the receiver. This means that the output is indeterminate. If this could happen in your application and you want there to be a defined state, I would recommend looking into fail-safe biasing.

    There is a short application note explaining how to do this below:

    http://e2e.ti.com/support/interface/industrial_interface/m/videos__files/264976.aspx

    Thanks,

    John