i.MX28 BCH compatibility with NAND

[RobertMGirard]

Hello all,

I have been getting more info on using non-ECC NAND Flash with the i.MX283 for our new design.

FYI: We have never used NAND before this design, so admittedly I have a lot of gaps in knowledge.

An issue has come up that I would like to get more info/opinions on regarding the capability of the internal BCH acceleration silicon to support newer/future NAND Flash.

According to a rep for Micron, the newer NAND Flash will require a 1k byte data block size for error correction.

The current silicon for the i.MX28 supports 900 bytes max ( 512 bytes typical ), which makes it a poor choice going forward for new designs with MLC (now) or SLC (soon).

Has anyone run into this issue, and if so, how are you working with this future limitation other than moving to serial NOR or ECC NAND ( both more expensive ).

Our product life will likely be about seven years, which is fine as far as the i.MX283 itself is concerned ( 15 year guaranteed lifespan ), but it seems like having to depend on non-ECC NAND Flash could limit it to way less!!

Thanks

Robert

[AhmetYUCE]

You can check Toshiba for NAND also. I'm not sure but i thing STMicro's moemory business line Numonyx bought by Micron.

[RobertMGirard]

Hello Ahmet,

Thanks for the comments.

My product actually needs very little memory actually - around 128 Mbyte max.

My concern is about availability for lower memory parts over the next 6 - 7 years, but I agree that there probably are better sources of NAND for "deeply embedded" product designs such as mine than Micron.

 I also learned just last Friday that one of our current products is using 1Gbit STMicro NAND. I got one of the chips and installed it on the EVK and it worked just fine, so yes, I agree with you that Micron and Samsung arent the only game in town for the type of Flash I can use with the i.MX28.

If you know of some other sources, that would be great info. I would like to have several sources going forward.

Thanks

Robert

[AhmetYUCE]

What is the size of NAND flash you need? SLC flash are more reliable and might be a little more expensive. For SLC usually 1 bit detection is enough. Micron recently changed die of some SLC flash parts. As far as i remember new parts needs 2 bit (or 4) correction capability. But competitors of Micron still produces parts with 1 bit correction is enough.