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Altera_Forum's avatar
Altera_Forum
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14 years ago

Warning: Found 20 output pins without output pin load capacitance assignment?

What is the method to find this info? Rough estimates usually adequate? Where do these numbers go into Quartus?
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

I got the same warning, because the default cap load is 0pF for the pin output type you have specified. If you go to the Assignments/Device... tab and click on the "Device and Pin Options..." button, you will find "Capacitive Loading" under Category:. Here you can set the default load cap for the output driver type in your design.

I find this useful for output timing analysis. It will also help you choose the minimum output drive strength to meet your desired output timing.