Forum Discussion
Daniel99
New Contributor
1 year agoRestricted Fmax due to minimum period
I have created a simple project with a 500 MHz clock fed into a clock pin set for LVDS. This clock goes only to a divide-by-4 block (two flip-flops) and the resulting 125 MHz is fed to an output pin....
Daniel99
New Contributor
1 year agoThank you Kenny! This makes perfect sense. However, if Quartus was a little more verbose about the restricted Fmax and mentioned the LVDS frequency limitation in this case it would of course be easier to understand.
The numbers you mention for I/O frequency restriction vs. the different speed grades, I cannot find in the device datasheet. Are they listed somewhere else?
I'll try your design!