4GB DDR3 Support

[suhasdk]

Hi Folks,

I have two queries to address:

1. Planing to use single rank 4GB DDR3 (1GB Device x 4) using single Chip Select (CS0) in one of our design. Please let us know whether i.MX6Q supports such memory organisation that is 4GB on single Chip select.
2. Pretty sure that i/MX6Q works fine with 533MHz DDR clock frequency. I have ambiguity in interfacing 800MHz DDR3 memory device with i.MX6. To be specific, whether MT41K512M16HA-125 IT micron device can be used in above mentioned memory organization.

Thanks & Regards,

Suhas D K

[MOW]

Hi Suhas

Last year for testing purposes we equipped some few of our own i.MX6Q-based boards with 4pcs 8 GBit (512M16) DDR3 RAM-Chips from Intelligent Memory in 64-bit bus-configuration, i.e. all 4 chips connected to a single chip-select. Although we were not able to perform elaborate tests due to mechanical problems with the chips on our boards -- the 8 GBit chips from IM are slightly larger than all other DDR3 chips we equipped so far and unfortunately collided with some filter capacitors placed too close to the RAM-chips on the boards -- we were able to get two of the test-boards to (partially) functioning state, execute some few runtime-tests, and access the 3.75 GByte of memory mapped to the CPU-address space in such a configuration.

So, yes: 4 GByte RAM connected to a single chip-select of an i.MX6Q do work.

While we haven't done any tests with the 8 GBit Micron type K you're asking for, we're using the 2 GBit and 4 GBit versions of these RAM-types without any problems in both DDR3-1066G amd DDR3-800E configurations and RAM-chips specified for higher clock-rates can be used at these clock-rates without any issues.

As far as I know, the i.MX6 SoCs do not support any DDR3 clock-rates faster than 533 MHz (DDR3-1066).

Regards,

Marc

[flournoy]

Hi Marc - 

Since the  i.MX6 docs are unclear on this point (4GB on single CS), can you comment on the MMDC register changes  that were required moving to 4GB?

Thanks,

Phil