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MLVD-SN65MLVD202D

BIlly Lam
Prodigy 20 points

Hi all,

We want to design a circuit to repeat the RS485 signal from 1 to 4 or 8 devices, please show us the application circuit in details to use the product in the way of M-LVDS repeater.

Thanks very much!

Billy Lam

  • 0
    TI__Mastermind 28265 points

    Billy please send me a corse diagram.

    RS485 can already connect up to multiple devices on one bus.

    Repeaters are only used for cable extensions.

    thanks, Thomas

  • 0 in reply to Thomas Kugelstadt
    Prodigy 20 points

    Hi Thomas

    Yes, actually we built a network with star connection not a daisy chian type, we don't want to rework those cabling.
    So we need such a repeater to fulfill the 485 communication. We got a motherboard and some devices in 485 protocol and circuit.
    We need to connect them up, that's great if we can build a device from 1 to many for 485 commucation, please advise!
     
    Thanks at all
    Billy

  • 0 in reply to BIlly Lam
    TI__Mastermind 28265 points

    Billy,

    I have asked around but no one had really experience with star configuration in RS485 circuits. Although 15 years ago I had worked with a customer on a star configuration, I won't say I'm knowledgable about it. The reason, changing from daisy-chain to star messes up the transmission line concept. You cannot terminate the star branches resistively. I recall using schottky diodes, which isn't really a termination but rather a clamping scheme. well, it worked. The drawback of a star is, that it is highly application dependent, that is it depends on the cable length and the media capacitance of each strang.

    I hope the schottky "termination" works for you and sorry to be of no further help.

    Regards, Thomas