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Virtex II - LVDS_33_DCI?

In the Virtex II User Guide (v1.6.1) on pg 200, it states ...

DCI in Virtex-II Hardware DCI only works with certain single-ended and differential I/O standards. DCI supports the following Virtex-II standards: LVDCI, LVDCI_DV2, GTL_DCI, GTLP_DCI, HSTL_I_DCI, HSTL_II_DCI, HSTL_III_DCI, HSTL_IV_DCI, SSTL2_I_DCI, SSTL2_II_DCI, SSTL3_I_DCI, and SSTL3_II_DCI, LVDS_25, LVDSEXT_25, LVDS_33_DCI, LVDS_25_DCI, LVDSEXT_33_DCI , and LVDSEXT_25_DCI.

Note the reference to LVDS_33_DCI! In several other places I have found it stated that if you use DCI with LVDS, then you must have Vcco = 2.5V, or it won't work correctly.

I would like to try DCI with my Virtex II LVDS inputs with Vcco = 3.3V, and have it work correctly. Can this be done? Or is there a typo in the User's Guide.

Reply to
Barry Brown
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The documentation is wrong; the V2 LVDS DCI input terminators only work at 2.5V, as they are implemented as a split termination between VCCO/GND on each side of the pair- the common mode LVDS offset voltage will be way off at VCCO=3.3V

See Xilinx Answer Record 15633 ( but ignore the incorrect 62.5 mW number )

For a handy list of other LVDS_xx_DCI 'features' that await, see also:

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Brian

Reply to
Brian Davis

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