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Altera_Forum's avatar
Altera_Forum
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12 years ago

AC Coupled LVDS vs DC Coupled LVDS

Hello to everyone, this time I´m coming to you with a question regarding the kind of coupling between the development board and the external devices where one would like to read or write data. ...
Altera_Forum's avatar
Altera_Forum
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12 years ago

AC and DC coupling of differential signals is discussed in these app notes:

http://www.ti.com/lit/an/scaa059c/scaa059c.pdf

http://www.ti.com/lit/an/scaa062/scaa062.pdf

https://www.idt.com/document/apn/lvds-pecl-termination-app-note

In your case, AC-coupling or DC-coupling clock-like signals is fine.

If the data lanes are AC-coupled, then those lanes would need to be modulated so that have no DC-disparity, either by a PRBS pattern or by 8/10B encoding.

Cheers,

Dave