Naturally, the first question is: “How do they do that?”
To get all the chips into the DIMM format Samsung uses TSV interconnects on the DRAMs. The module’s 36 DRAM packages each contain four 8Gb (1GB) chips, resulting in 144 DRAM chips squeezed into a standard DIMM format. Each package also includes a data buffer chip, making the stack very closely resemble either the High-Bandwidth Memory (HBM) or the Hybrid Memory Cube (HMC).
Since these 36 packages (or worse, 144 DRAM chips) would overload the processor’s address bus, the DIMM uses an RDIMM protocol – the address and control pins are buffered on the DIMM before they reach the DRAM chips, cutting the processor bus loading by an order of magnitude or more. RDIMMs are supported by certain server platforms.
Every so often something very strange happens that puzzles The Memory Guy. On December 29 (or Dec. 30 in Seoul) something odd occurred.
I received two e-mails, one from SK hynix at 3:55 PM Pacific Time, and one from Samsung exactly one hour later. Both were press releases.
The SK hynix release was titled: “SK Hynix Developed the World’s First Next Generation Mobile Memory LPDDR4”. It announced that the company is sampling its 20nm-class 8Gb LPDDR4 DRAM to customers.
The Samsung release was Continue reading
Just in case anyone thought that NOR flash was not going to get any denser, Spansion announced a single-chip 8Gb parallel NOR today. This product, built using Spansion’s MirrorBit technology on a 45nm line is not only the densest monolithic NOR chip on the market, it’s also the NOR flash with the finest process technology.
Spansion’s GL-T product is aimed at applications that need high densities at read speeds faster than those that NAND flash can deliver. Spansion tells The Memory Guy that read performance is 95MB/s and program performance is 1.8 MB/s.
Sampling will commence in December, with production in the first quarter of 2013.