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Altera_Forum
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10 years ago

Cyclone V speed is much slower

Hello. I am new to Cyclone V. I took my design for Cyclone III and recompiled it with Quartus II web 13.1. From the timing analyzer, I can see that the maximum clock rate is only 84 Mhz while I was...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
10 years ago

Do note that Cyclone V using ALTERA_PLL ip instead of ALTPLL which is used for previous device family like Cyclone III and Cyclone IV.

Agree with nicejob comment, you may need to consider the speed grade of the device used. Do counter check the timing spec of Cyclone V device and compare to other previous series device timing spec in their I/O timing spreadsheet.

https://www.altera.com/content/dam/altera-www/global/en_us/others/literature/hb/cyclone-v/cyclonev-io-timing.xls

https://www.altera.com/content/dam/altera-www/global/en_US/others/literature/hb/cyclone-iv/cycloneiv_io_timing_qii10_0.xls