Can Spartan-6 Support M-LVDS ?
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From: ajpanicker on 9 Apr 2010 10:01 Does the Spartan-6 LX family or Spartan3A support the Multipoint-LVDS specifications? We need input and ouput buffers compliant to M-LVDS type1 and types 2. Also , the buffers should be 5V LVTTL tolerant.
From: austin on 9 Apr 2010 11:05 a, If it is not in the data sheet, then it isn't supported. I have no idea what "multi-point" LVDS is: sounds like someone's idea of how to ruin a perfectly good point to point IEEE standard! OK, I just read about it on Wikipedia, and that confirms my suspicions ... There is the "bus-LVDS" which we 'invented' and supported, but the signal integrity of that is a compromise at best, and I have never really liked to deal with it at all. Regardless, it does work (within its limits). For 5v tolerance, I suggest level shifters, or using resistors. At these advanced technology nodes we are lucky to be able to still use 3.3v IO! Austin
From: Eric Smith on 9 Apr 2010 13:08
> Also , the buffers should be 5V LVTTL tolerant. Which? 5V, or LVTTL? They are two different things. IIRC, Spartan-6 does support LVTTL. It does not support 5V I/O directly. |