Hi Chris,
thank you for your reply, my problem was AD7190 was damaged, I think the reason was we don't care about ESD and we touched it directly.
Now we have a reliable communication with FPGA Xilinx Spartan 3.
my offer to someone who want to work with this IC, is pull up the SYNC Pin at first and see the DOUT Pin it should have PWM in output, if it work your AD719x is healthy else your bias or your ADC have a problem.