iMX27 and SDRAM: LPDDR, SDR and.. not DDR?

[rd_cet]

Looking at MX27 datasheet it looks like there is not support for DDR.

Indeed it would be really useful to be able to use common 2.5V DDR instad of LPDDR.
Can anyone give some advice on how  to interface with DDR? If possible in a reasonable manner..
Thanks

[fabio_estevam]

Take a look at the MX27 Reference Manual. MX27 does support DDR.

I suggest you to look at some of the MX27 development tools schematics for reference.

Regards,

Fabio Estevam

[rd_cet]

Hello.
On both MX27 ADS and PDK schematics there is a LPDDR memory, no schematics with DDR.
From the logic point of view there's not difference between DDR and LPDDR, more or less. But looking at the datasheet (pag. 41) I see
"I/O Supply Voltage, DDR" at 1.8V and I don't know if this can be a problem if connecting 2.5V DDR.

Am I missing anything?

Thank You.


Message Edited by rd@cet on 2009-01-16 10:24 AM

[fslaficionado]

The datasheet says that the limit for the DDR pads is 1.8V. So you wouldn't be able to use regular DDR, which is 2.5V. You'll have to use mDDR, at 1.8V.

[rd_cet]

Yes, I think it too. I was asking if there is any way (some electrical fix) to do it. But probably there is not any  safe and cost effective fix.

[Wayne84]

This processor can only suppport low power DDR which is 1.8V, so you cannot use DDR with 2.5V.