PicoZed 7030 Net Lengths

Question

Hi,

We are designing carrier board for PicoZed 7030. We will use high speed differential signals(500MHz). Thus; knowing the signal lengths is essential for our design.

Does the given "Routed Net Lengths Table" consist FPGA internal net lengths and via lengths?

Thanks,
Muhammet

Former Member · Accepted Answer

Hello Muhammet,

Here is the guidance from our engineering team:

The 7030 Net Length report that is posted are the physical net lengths on the board.

The end customer should take the PZ7030 net length report + the 7030 package delay file + the expected delay in their carrier into account when doing their analysis if they want to achieve a high performance interface.

Then they should use common guidelines for matching to achieve 500Mb/s. The Vita57 FMC spec says < 200ps of skew to achieve this. If you use 167ps/in (2ns/ft) average prop delay in FR4, total skew can be an inch and you can achieve 500Mb/s.

So, net length + package delay + carrier delay < 167ps or 1 inch should cover them.

-Gary