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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 donīt 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 donīt contact me via PM, because there is no time to respond to them. No friend requests. Thank you.



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