03-29-2012 09:39 AM
So I have a shiny new SP605 and the XM105 to go with it. I'm in the process of designing a video/audio-capture card, and will be debugging it on the XM105 before making an FMC variant.
I was wondering about the voltage robustness of the S6's pins. I know they're running at 2.5v on the FMC card, so does that mean I need to put QuickSwitches (or similar) in place in-between my 3.3v logic on the expansion card and the connection to the FPGA ?
Normally I'd assume so, but I read "somewhere" last night (sorry, new baby, which means lots of extra time for reading the web while feeding/rocking-the newborn-to-sleep (iPad's are great!), but very little actual sleep...) that the S6 would be ok if a 3.3v signal was presented as an input on the expansion lines... Driving 2.5v will be fine (anything above 2v will count as logic-high) but I don't want to blow up the nice new card before I really get any use out of it!
Solved! Go to Solution.
03-29-2012 09:57 AM
I'm worried I'm missing some nuances with this question, so I'll make a generic statement.
Spartan-6 inputs, regardless of bank voltage can safely receive 3.3v signals.
Check out the Vin spec in the data sheet:
As far as I'm aware the XM105 is just creating a short to the FPGA.
03-29-2012 10:19 AM
Nope - no nuances. I'm rarely accused of being subtle [grin]
Thanks for that - I did in fact have table-2 in ds162 open in front of me, but somehow I missed the "All i/o standards" part of the description... I'll get rid of the Quickswitches then :)