JEDEC publishes SPHBM4 standard for organic-substrate memory

JEDEC Solid State Technology Association has published JESD330-4: Standard Package High Bandwidth Memory, defining SPHBM4 for memory packages that use the same DRAM dies as HBM4, which is commonly used in AI accelerators. The standard pairs those dies with a new interface base die that supports mounting on standard organic substrates instead of silicon substrates.

JESD330-4 SPHBM is designed to deliver the same aggregate data throughput as HBM4 with fewer pins by running at a higher frequency. While the HBM4 interface has 2048 data signals, SPHBM4 will define 512 data signals with 4:1 serialization to reach the same bandwidth, enabling the relaxed bump pitch needed for organic substrate connections. JESD330-4 is available for download from the JEDEC website.