Honored ContributorFor EP4CE30F23C6N device, what is its max clock to drive external ddr2? I just find one statement on handbook "support to DDR2 SDRAM interface up to 200Mhz"
Where I can find the detail specification about my concerns? I need to have this clock value to estimate the data buffer bandwidth. Thanks a lot.
Honored ContributorAltera's DDR2 SDRAM interface IP doesn't support operation above 200MHz in -6 speed grade (fastest) Cyclone IV parts. This will be the limit if you wish to use Altera's IP.
Cheers, AlexHonored ContributorThanks for your reply. Does this mean the best case the cyclone iv device with -6 speed grade is able to run under 200Mhz DDR2 clock?
Honored ContributorThe practical answer - yes. If you wish to use Altera's DDR2 IP.
Cyclone IV will support much higher external clock output frequencies. Refer to the PLL Specifications in the cyclone iv device datasheet (https://www.altera.com/content/dam/altera-www/global/en_us/pdfs/literature/hb/cyclone-iv/cyiv-53001.pdf), and table 1-25. A -6 part will support up to 472.5MHz, depending on I/O standard. However, putting that to use as part of a DDR2 interface is another matter and not something to be undertaken lightly. Cheers, AlexHonored Contributortks a lot!!!!!!!
