I am currently designing a heatsink solution (heatsink + thermal pad) for a FPGA Ultrascale with a lidless package (XCKU035 FBVA900).
I have read in ug575 some recommendations about heatsink attachment for lidless package.
But what about the applied pressure on the lidless FPGA?
We can read page 326 :
"Xilinx recommends that the applied pressure on the package be in the range of 20 to 40 PSI for optimum performance of the thermal interface material (TIM) between the package and the heat sink."
Is it the same for lidless flip-chip than lidded flip-chip ?
Thank you for your answer,