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User IO pin vs PLL_CLKOUT0N pin. Can I output a clock on user IO?

JDeff
Beginner
538 Views

What is the difference between the CLKOUT pins and user IO pins? The fitter allows routing of a pll clock output to a user IO pin. What is the difference? Will I get better performance or timing closure if I use the dedicated clkout pin? Right now I am using a single ended clock and its routed to a IO pin, but I am getting poor results and timing closure problems. Wondering if it is worthwhile to spin the board to use a dedicated clkout pin.

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1 Solution
JonWay_C_Intel
Employee
210 Views

The clkout is a dedicated path from the PLL to output pin. In zero delay buffer mode, the delay by the output pin is compensated. https://www.intel.com/content/www/us/en/programmable/documentation/mcn1401782837027.html#mcn14018696...

 

The fitter allows your PLL to output to user io pin via global routing.

 

Will you get better performance? To find out, you will need to analyze timing given the PLL compensation mode and routing to the clkout pin.

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JonWay_C_Intel
Employee
211 Views

The clkout is a dedicated path from the PLL to output pin. In zero delay buffer mode, the delay by the output pin is compensated. https://www.intel.com/content/www/us/en/programmable/documentation/mcn1401782837027.html#mcn14018696...

 

The fitter allows your PLL to output to user io pin via global routing.

 

Will you get better performance? To find out, you will need to analyze timing given the PLL compensation mode and routing to the clkout pin.

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