GXB_GND connection for Cyclone IV GX

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Hi,

I am using Cyclone IV GX FPGA. I am making use of the PCIe hard IP.

I want to know how the GXB_GND pins need to be connected. Can I connect it directly to GND.

The pin file shows that unused GXB Receiver or dedicated reference clock pin are to be connected to GXB_GND through a 10 KOhm resistor.

But I don't find anywhere in the Cyclone IV handbook how to connect the GXB_GND.

Can someone please help me out.

regards,

rajesh

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Hello, atrajesh !

I have the same question.

Did You find the answer?

Which of the 2 solutions are legal for Cyclone IV GX FPGA:

1). connect both unused dedicated reference clock ( REFCLK1n and REFCLK1p ) pins directly to PCB GND plane.

2). connect one unused dedicated reference clock REFCLK1p pin directly to PCB GND plane, but use another one from the pair ( REFCLK1n ) for reference clock.

P.S. The question is because I don't have enough space on PCB to place 10 KOhm resistor from unused REFCLK to GND.