[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Xylo-SDR] LVDS buss topologies



National Semiconductor makes parts specifically designed for
multi-drop LVDS applications on a backplane.  These parts are able to
drive loads down to 26 ohms (due to multiple 100 ohm terminations). 
The DS96LV010 (check part number) is a good example.  It is commonly
used to move a high frequency clock around a backplane.

73 de Phil C

On 2/21/06, Eric Ellison <ecellison@comcast.net> wrote:
>
>
>
> Ray
>
> I'm showing my ignorance, but I was under the impression that LVDS used
> twisted pair and was not a 'buss friendly' design.
>
> Multi-drop would seem logical, since folks already have other designs in
> mind for buss mounted cards.
>
> Thanks
>
> Eric
>
>
>
>
>
>  ________________________________
>
>
> From: xylo-sdr-bounces@lists.ae5k.us [mailto:xylo-sdr-bounces@lists.ae5k.us]
> On Behalf Of Ray Anderson
>  Sent: Tuesday, February 21, 2006 5:26 PM
>  To: xylo-sdr@lists.ae5k.us
>  Cc: Ray Anderson
>  Subject: [Xylo-SDR] LVDS buss topologies
>
>
>
>
> At the following URLs there are  Visio and JPEG drawings of  3 common LVDS
> buss topologies (Point to Point, Multi-Drop, and Multi-point) that might be
> found on a backplane. Each comes with it's own challenges and problems.
>
>
>
>
>
> http://www.hamsdr.com/dnld.aspx?id=144     (Visio format)
>
>
>  http://www.hamsdr.com/dnld.aspx?id=145     (.jpg format)
>
>
>
>
>
> In the case of the Point to Point topology there is a single driver on the
> buss and multiple receivers. In the Multi-Point topologies there can be
> multiple drivers as well as multiple receivers. If I am interpreting the
> Janus and Lionheart block diagrams correctly it seems that the currently
> envisioned topology is point-to-point (Janus and Lionheart only). With the
> desire for extra backplane slots it looks like Multi-Drop. Are there
> applications envisioned in the future that might place multiple drivers on
> the buss in the Multi-point topology?
>
>
>
>
>
> -Ray    WB6TPU
> _______________________________________________
> Xylo-SDR mailing list
> To post msg: Xylo-SDR@ae5k.us
> Subscription help:
> http://lists.ae5k.us/listinfo.cgi/xylo-sdr-ae5k.us
> Xylo-SDR web page: http://xylo-sdr.ae5k.us
> Forum pages: http://www.hamsdr.com/hamsdrforum/
> Archives: http://lists.ae5k.us/pipermail/xylo-sdr-ae5k.us/
>
>