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ISOW7843: transfer distance

Intellectual 930 points

Replies: 7

Views: 162

Part Number: ISOW7843

I like check if this part good for transfer the PPS signal for example for a 1.5KM to 2KM distance? 

The PPS signal can be 3.3V or 5V LVCMOS/LVTTL or CMOS/TTL.

Otherwise, do you have any recommendations? Thank you.

  • Hi there,

    Currently our ISOW expert is out of office. However, I will do my best to help. 1.5KM to 2KM seems rather long. Have you considered using a differential transceiver, like the ISO1410, instead? 

    Respectfully,

    Lucas

  • In reply to Lucas Schulte9:

    Yes, differential is fine or preferred. 

    I was think RS-422 and or RS-485, however looks like RS-422 is ~ 1.5KM max and RS-485 is 1.2KM max. 

  • In reply to new2day:

    These "maxes" are probably not taking into account PPS (1Hz) signals. Generally the slower the data rate, the longer cable you can get away with.  However, the signal will be subjected to the capacitance and resistance of the long cable. This could cause rise times to be slower and introduce propagation delay. Are there any strict requirements surrounding your PPS signal?

  • In reply to new2day:

    optical transceiver (or driver/receiver) is fine too. Thanks.

  • In reply to Lucas Schulte9:

    PPS is one kind of signal to be transferred. Our clock is 100MHz or greater (e.g. 250MHz) and we need 0 or < 100ps skew amount multiple of this transceivers or drivers/receivers. 

  • In reply to new2day:

    To clarify, in addition to PPS you also want to transmit >100MHz signals over this 1.5KM to 2KM distance? If so, RS485 or differential signaling will not handle that.

  • In reply to Lucas Schulte9:

    Hey new2day,

    I haven't heard from you but I hope I was able to help somehow. If you truly are trying to send 100MHz+ signals over 1.5KM distance, then unfortunately this is currently out of the capabilities of our digital isolators. This application may be better suited for fiber optic.

    I'm going to close the thread but feel free to start a new one if you want to continue this conversation in the future.

    Respectfully,

    Lucas