Should I use AC or DC coupling when implementing the SerialLite II Protocol?

Description

The Stratix® IV GX and GT transmitter can be DC-coupled to a Stratix IV GX and GT receiver for the entire operating data rate range of Stratix IV GX, from 600 Mbps to 8.5 Gbps.

If your FPGA SerialLite® II interfaces with a 3rd party device then Altera® recommend AC coupling.

You should perform signal integrity simulations on your transceiver interface to ensure device compatibility.