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SN65HVD72: RS485 with AutoDirection

Part Number: SN65HVD72

Dear Sir 

May I know which TI solution can support RS485 AutoDirection ,just like MAX13487E/MAX13488E


  • Hi Kai,

    TI does not have a transceiver which is directly compatible, although similar behavior can be achieved with a standard RS-485 transceiver by implementing failsafe termination (A pin pulled high, B pin pulled low), tying the D input low, and then controlled DE to be high to send "zero" bits and low to send "one" bits.

    Another way of implementing automatic direction control of an RS-485 transceiver is to use a monostable multivibrator to enable the transceiver whenever a data frame causes the D input to toggle. Here is a reference design implementing this approach:


    This circuit has the advantage of maintaining RS-485 compliance by actively driving both the "one" and "zero" levels.

    I hope this helps - please let me know if you have any other questions.