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  1. #1
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    Isolated Converter RS-422

    Hi,

    Because of problem of Noise, I search for isolated converter device from UART to RS-422 based on optic and not with switching regulator.

    The communication data rate is 115200 bits/Sec.

    Anyone familiar with these devices ?

    Thanks.

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  2. #2
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    Re: Isolated Converter RS-422

    RS-422 should have high noise immunity already.
    If you can build yourself, UART->Opto->ADM488 or ADM489 would work and be simple. Keep the opto on the UART side where there is only one data line.

    Brian.
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  3. #3
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    Re: Isolated Converter RS-422

    Hi Brian,

    I look on Vishay for opto couplers at the UART side, The rise/fall time for the fastest device (VOT205AT) is slow 3uSec, for data rate of 115200 the bit is 8.6uSec, so i will remain only with 8.6uSec-3-3=2.6uSec which looks very small value, Do you familiar with high speed couples ?

    Thanks.



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    Re: Isolated Converter RS-422

    Hi,

    I don´t understand.
    Isolated but with no switching regulator.

    Due to the RS-422 you need energy to drive the 50 Ohms impedance signal lines. Where does this energy come from? Battery? Solar cell?

    Klaus
    Please don´t contact me via PM, because there is no time to respond to them. No friend requests. Thank you.



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