JEDEC Releases New Standard for LPDDR5/5X Serial Presence Detect (SPD) Contents

ARLINGTON, Va.-- August 22, 2024 -- JEDEC Solid State Technology Association, the global leader in standards development for the microelectronics industry, today announced the publication of the JESD406-5 LPDDR5/5X Serial Presence Detect (SPD) Contents V1.0, consistent with the updated contents of JESD401-5B DDR5 DIMM Label and JESD318 DDR5/LPDDR5 Compression Attached Memory Module (CAMM2) Common Standard. To download these and other published JEDEC documents, visit the JEDEC website.

JESD406-5 documents the contents of the SPD non-volatile configuration device included on all JEDEC standard memory modules using LPDDR5/5X SDRAMs, including the CAMM2 standard designs outlined in JESD318. The JESD401-5B standard defines the content of standard memory module labels using the other two standards, assisting end users in selecting compatible modules for their applications.

JESD406-5 standard specifies the contents of each SPD byte, allowing application software including BIOSes to determine the module capacity, speed, I/O configuration, and content revision level of the module. Rounding algorithms are defined to optimize performance even when legacy modules are plugged into new systems, or new modules are plugged into legacy systems.

JESD406-5 supports the memory module configurations, known as “raw cards”, as documented in the JESD401-5B specification. CAMM2 Raw card E defines an LPDDR5/5X module usable as one or two ranks of memory organized as eight subchannels, each with x16 I/O interface. Module design is in process and will be available on the JEDEC website once system qualification and standard design approval is completed.

“The release of LPDDR5/5X SPD Contents is an important step in expanding the market for these components, including use in notebook computers. Combined with standards for module base specifications and labels, system designers can be assured of consistent support for incorporating LPDDR5 devices into their systems,” said Mian Quddus, Chairman of the JEDEC Board of Directors. “With detailed algorithms for using the parameters in the SPDs, end users can be assured of optimal performance.”

About JEDEC

JEDEC is the global leader in the development of standards for the microelectronics industry. Thousands of volunteers representing over 350 member companies work together with more than 100 JEDEC technical committees and task groups to meet the needs of every segment of the industry, manufacturers and consumers alike. The publications and standards generated by JEDEC committees are accepted throughout the world. All JEDEC standards are available for download from the JEDEC website. For more information, visit www.jedec.org.