Virtex-E: Can we tie Vcco to 2.5 V for LVDS, and have LVTTL inputs?
LVTTL input buffers require a VCCO of 3.3V and are incompatible with the VCCO requirement for LVDS outputs which require 2.5V. The LVCMOS2 standard requires a VCCO of 2.5V and can be used in the same bank as LVDS outputs. The LVCMOS2 buffers are 3.3V tolerant, but with slightly lower Vil and Vih thresholds. For most applications the LVCMOS2 input thresholds are acceptable.