Dual SODIMM connected to LS1046A

[smiller2]

The LS1046A appears to have four DDR chip selects but supplies only two DDR clock outputs.   The design requirement is to have two SODIMM slots. The base configuration would have 16GB of DRAM in a single rank.  The upgrade configuration  would allow an additional 16GB of single rank DRAM to be added to the other slot.   With only two clock outputs from the LS1046A,  I would guess that each SODIMM would get one clock pair a piece on the primary pair?  

Has dual DIMM slots been done on the LS1046A?    The reference design show only a single slot of a full width module.    I am worried about the memory configuration because the previous design used DDR3 to the SoloX  and we got burned when we assumed that multiple ranks were supported and it was not the case. 

Thanks. 

[ufedor · Accepted solution]

You wrote:
> The base configuration would have 16GB of DRAM in a single rank. 
> The upgrade configuration  would allow an additional 16GB of single rank DRAM to be added to the other slot.
Described configuration is viable because LS1046A DDR controller supports two complete sets of control signals - i.e:
MCS0, MODT0, MCKE0
MCS1,  MODT1, MCKE1

> I would guess that each SODIMM would get one clock pair a piece on the primary pair?
Correct.

> Has dual DIMM slots been done on the LS1046A?
There is no such design from NXP.

[NimeshRana]

Hello NxP Tech Support team, 

With respect to same above query, we are also planning to use dual DIMM socket to support the two 16GB DDR4 (total 32GB DDR4 memory interfaced with LS1046A). 

Attached here the architecture we are planning to implement to support dual DIMM with LS1046A. 

planned configuration to support dual DIMM memory interface

Please review it and provide your input where changes needed to support 2 x 16GB DDR4 working simultaneously  to fulfill requirement of 32GB DDR4 memory. 

Waiting for the quick support. 

Regards,

Nimesh