Vicm for REFCLK in Cyclone IV GX

Hi everyone!

I'm developing PCB based on CIV GX.

I use schematic of "CIV GX DevKit Board" as reference.

(http://www.altera.com/products/devkits/altera/kit-cyclone-iv-starter.html)

There is mismatch between CIV Handbook and reference schematic.

Namely, it is recommended to use Vicm = 1100mV for REFCLK input in Handbook (quote: "...needs off-chip resistor to restore Vcm").

But I don't see using of Vicm in reference schematic. There is only one 100 Ohm resistor as termination of LVDS near REFCLKp/n pins.

What is right ?

Thank you.