Spartan-3e order of availability?

It used to be that packages were simple and cheap. The TQ144 is really
just a lead-frame for direct bonding to the die pads, and some plastic
on either side.
FT256 is a much more complicated package, a multi-layer pc-board at the
bottom that routes all die pads from the periphery to their individual
locations that are evenly spread over the package area. And the routing
is done with attention to the characteristic impedance, to avoid
reflections.
The result is much better signal integrity, and a smaller packege, i.e.
potentially a smaller pc board.
You pay for that with a few dollars at these single-quantity prices.
Of course far less in production quantities...

When it comes to really large, 1500-ball packages, there are:
10 metal layers on the die, 10 metal layers in the package, and perhaps
10 to 20 layers in your pc board.
Maybe the electrons go dizzy with all this complicated routing...
Peter Alfke

Peter,

I understand that FT256 is a more complicated package than TQ144. But
why does it (the FT256 package) have a very heavier price impact on
XC3S400 than on XC3S200? Can I expect the same for Spartan3E?

Andrew,

"Who knows how Xilinx do their pricing,"
Yes, but I don't feel good when something looks illogical to me!

Luiz Carlos