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Altera_Forum
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11 years ago

What IO standards should I choose for PCIE signals?

Hello: I am using cyclone IV GX, Should I choose 1.5v PCML for PCI-E data out and PCI-E data in? Should I choose HCSL for PCI-E reference clock in? I can't find any documents about ...
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Altera_Forum
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10 years ago

Hi ridgemao,

For the refclk IO standard information, you could refer to Table 1–6. REFCLK I/O Standard Support in the Cyclone IV Device Handbook, Volume 2. There it is stated that you could use HCSL for PCIe refclk with DC coupling. If you are using AC coupling, then you can choose from LVDS, LVPECL and PCML.

As for the CIV TX, it only support 1.5V PCML. CIV RX can take LVDS, LVPECL and PCML.