Forum Discussion
Altera_Forum
Honored Contributor
8 years agoNot always, though SDRAM controllers often need their own PLLs, especially if they are connected to DDR. It may not be practical to run the system clock from this PLL. But Ive seen systems where there SRAM was run at the system clock frequency, others where the memory clock domain was the same speed as the system clock, but for reasons of architecture, were asynchronous clocks.
If you have several data sources all connected to the same ram, you may need to run at a different clock speed for reasons of bandwidth. But its all a question of system design.