UCIe Consortium Releases 4.0 Specification on November 12 With On-Package Memory Link at Up to 93.75 Percent Data Efficiency and About 2.5 TB/s/mm Bandwidth Density
The UCIe Consortium released the UCIe 4.0 Specification on November 12, moving the chiplet interconnect standard from die-to-die connectivity toward system-level integration. The headline addition is UCIe.mem, the first standardized on-package memory link between compute dies and memory dies. It defines how systems on chip talk to memory logic dies while using existing memory technologies such as HBM and LPDDR.
Figures published by the consortium put UCIe.mem data transfer efficiency at up to 93.75 percent, with die-edge bandwidth density of approximately 2.5 TB/s/mm. The consortium said the design separates memory control from the compute side, allowing on-package memory bandwidth to scale with system and workload needs.
On connection density and power, co-optimized link profiles in the 4.0 specification deliver 30 to 80 percent greater energy efficiency. The enhanced UCIe-S bump map for 48 GT/s and 64 GT/s provides about 20 percent greater shoreline bandwidth density and about 10 percent greater area bandwidth density. The consortium noted that the efficiency figures apply to the die-to-die communication link itself and do not mean system-wide power consumption falls by the same proportion.
For security, the 4.0 specification introduces Trusted Reporting of Chiplet State, or TRoCs, which lets a package report the state of its dies over integrity-protected two-way management channels. The specification also enhances status monitoring and fault notification across multiple dies.
UCIe 4.0 is fully backward compatible with all previous UCIe specifications. The specification and an accompanying white paper are available by request at uciexpress.org. The white paper was written by Debendra Das Sharma of Intel, chairman of the UCIe Consortium. The announcement materials gave no timing for compatible products or mass production.
Source: UCIe Consortium
Published by GSM · USA (original Chinese edition)
Photo: 图：UCIe 封装内内存连接示意图。来源：UCIe 联盟官方发布。 / Photo: Diagram of UCIe on-package memory connectivity. Credit: UCIe Consortium.
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