I had a board which mounted Virtex 155. I've
changed  the FPGA to
Virtex 220.
The support engineer of Xilinx sales company said both FPGAs were
compatible and there was no problem.
But all 4 board I changed FPGA don't work at all. Even JTAG interface
doesn't work.
Are they actually compatible? Or do we need to modify the board to
mount Virtex 220?

 
Kazu

On May 26, 12:52=A0pm, Kazu
<cygnet.s...@gmail.com> wrote:
> I had a board which mounted Virtex 155. I've changed =A0the FPGA to
> Virtex 220.
> The support engineer of Xilinx sales company said both FPGAs were
> compatible and there was no problem.
> But all 4 board I changed FPGA don't work at all. Even JTAG interface
> doesn't work.
> Are they actually compatible? Or do we need to modify the board to
> mount Virtex 220?
>
> Kazu

Virtex 5 devices in the same package should be pin compatible.
Note that Virtex 5 LX and LXT parts are not pin compatible, but
their packages are also slightly different.  For example
if you had the V5LX155T you can't go to a V5LX220 (no "T").

If that's not the issue, I would suggest taking a look at your
power supplies to be sure you have enough current for the larger
part.

Regards,
Gabor