On-Package Memory with Universal Chiplet Interconnect Express (UCIe): A Low Power, High Bandwidth, Low Latency and Low Cost Approach

Emerging computing applications such as Artificial Intelligence (AI) are facing a memory wall with existing on-package memory solutions that are unable to meet the power-efficient bandwidth demands. We propose to enhance UCIe with memory semantics to deliver power-efficient bandwidth and cost-effective on-package memory solutions applicable across the entire computing continuum. We propose approaches by reusing existing LPDDR6 and HBM memory through a logic die that connects to the SoC using UCIe. We also propose an approach where the DRAM die natively supports UCIe instead of the LPDDR6 bus interface. Our approaches result in significantly higher bandwidth density (up to 10x), lower latency (up to 3x), lower power (up to 3x), and lower cost compared to existing HBM4 and LPDDR on-package memory solutions.