Multiple DIMM circuits or instantiations are presented in a single module.
In some embodiments, memory integrated circuits (preferably CSPs) and
accompanying AMBs, or accompanying memory registers, are arranged in two
ranks in two fields on each side of a flexible circuit. The flexible
circuit has expansion contacts disposed along one side. The flexible
circuit is disposed about a supporting substrate or board to place one
complete DIMM circuit or instantiation on each side of the constructed
module. In alternative but also preferred embodiments, the ICs on the
side of the flexible circuit closest to the substrate are disposed, at
least partially, in what are, in a preferred embodiment, windows,
pockets, or cutaway areas in the substrate. Other embodiments may only
populate one side of the flexible circuit or may only remove enough
substrate material to reduce but not eliminate the entire substrate
contribution to overall profile. The flexible circuit may exhibit one or
two more conductive layers, and may have changes in the layered structure
of have split layers. Other embodiments may stagger or offset the ICs or
include greater numbers of ICs.