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Altera_Forum
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15 years ago

Matching Cyclone III Signal Impedance to 65Ohm cPCI Traces

I am using an EP3C55F780I7 device to act as an interface between my peripheral board and a cPCI backplane. By specification, cPCI signal traces must be 65 Ohms +/- 10%. In reading through the various...
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Altera_Forum
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15 years ago

Dave,

Thank you. It's good to know that I shouldn't need to be too concerned about length matching. In talking with my manager, we are looking to make sure this board works in a cPCI system rather than looking to call this board cPCI-compliant which, in turn, removes a lot of worry as well.

Due to wanting to keep the non-PCI FPGA logic separated as much as possible from the PCI portion, I had already put a separate oscillator in my design...I had not thought about using it to verify the incoming PCI frequency, though. I like that idea.

-Jim