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Altera_Forum
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16 years ago

DDR2 SDRAM termination

In the CYCLONE||| development kit host board there are termination resistors present on the board for the DDR2 SDRAM. Termination is already included inside the DDR2 SDRAM chips. So why are the termi...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

I'm currently designing a board with an Cyclone III or Cyclone IV and attached DDR2 memory.

Is there a recent reference design (layout, schematic, quartus design) available which corresponds to the recommendations stated in "External Memory Interface Handbook Volume 2: Device, Pin, and Board Layout Guidelines" (emi_plan.pdf).

In particular, I'm interested in the termination scheme. Which termination resistor is really needed and where has it to be placed on the pcb?