Hello,

I am working with Atmel's AT91SAM9G45 ARM9 processor and have run in to an interesting issue. We based our first design of a product off of a development board which was using DDR2 memory. However, if the DDR runs over the AHB @ 133 MHz, what advantage is there to using DDR2? If I understand correctly, DDR2 and DDR operating at 133MHz will have the same memory bandwidth, with DDR having lower latency (smaller prefetch) and DDR2 consuming less power (and running at 1.8V which can be convenient vs having a 2.5V line on your power supply).

I feel like I am missing something. I am also unsure of how useful having a lower CAS latency is in terms of our normal use case (we execute some code in DDR as well as static memory allocation). If you can correct some of my misconceptions or help me shed some light on this subject, I would appreciate it.

Cheers,
Ben