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What is the max ddr2 clock frequency support by cycloneiv?

Altera_Forum
Honored Contributor II
1,976 Views

For 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.
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4 Replies
Altera_Forum
Honored Contributor II
1,241 Views

Altera'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, 

Alex
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Altera_Forum
Honored Contributor II
1,241 Views

Thanks 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?

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Altera_Forum
Honored Contributor II
1,241 Views

The 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, 

Alex
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Altera_Forum
Honored Contributor II
1,241 Views

tks a lot!!!!!!!

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