Help, I've been trying to find a definitive answer to this question. Can I connect Virtex II pins configured as pure outputs (LVCMOS33 or LVTTL) directly to 5v LSTTL, ACT, or FCT INPUTS without any resistors and not risk any damage ?
I've used the quickswitch design from the appnotes for my bidirectional pins, and 175 ohm series resistors for 5v TTL inputs to the Virtex II, but I tied the fpga outputs directly to 5v input logic pins and now I think I have a Virtex II part failure.
Any feedback greatly appreciated.
Thanks Jim