Ivan A. wrote:
> Do  anybody konwn why the core current of Virtex or Spatran-II is so
> large and the situation is worser when at low temperature.


Like earlier SRAM -based FPGA have this problem, you look at their 
documents.

which documents? Pls give me more information.

see attach files.

by the way ,the situation happens not only at low tempture, but also at 
high tempture. you should choose a good power chip.

good luck!