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Altera_Forum
Honored Contributor I
815 Views

Maximum Performance of DDR2 ALTMEMPHY on Cyclone-III

Hi 

 

I have a design, using DDR2 and ALTMEMPHY on the Cyclone-III. My DDR2 IOs are on the side of FPGA (Row IO). According to the 2008 release of AN-445, maximum clock rate of the ALTMEMPHY is 167 MHz for side IOs, 150 for Wraparound IOs, and 200 for top/bottom IOs. 

AN-445 of 2009 has increased max. clock rate to 167 for wraparound IOs. There is no newer release of this AN. 

On the other hand, on the Cyclone-III latest handbooks or datasheets there is no information on the maximum clock rate of ALTMEMPHY. 

 

I need 200 MHz clock rate for my DDR2 interface which is on the row IO, but I cannot be sure its timing is met on the memory side (due to the ambiguity of the datasheet). 

 

What is the maximum clock rate of DDR2 ALTMEMPHY on Cyclone-III devices? 

 

Thanks
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3 Replies
Altera_Forum
Honored Contributor I
53 Views

I have already tested a 200 MHz ALTMEMPHY DDR2 on the row IO (on the side of FPGA) and it worked, but I must be sure that it will work on the other boards in the mass production line. Any comments?

Altera_Forum
Honored Contributor I
53 Views

msj - 

 

Check out this external memory interface spec estimator: 

 

https://www.altera.com/products/intellectual-property/best-in-class-ip/external-memory/support-selec... 

 

According to this the limit for Cyclone III is 167MHz for row I/O in C6 speed grade, 150MHz for C7, and 133MHz for C8.
Altera_Forum
Honored Contributor I
53 Views

Thanks rsefton

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