JEDEC Published JESD79-5C DDR5 SDRAM Standard

JEDEC Solid State Technology Association announced publication of the JESD79-5C DDR5 SDRAM standard.

This important update to the JEDEC DDR5 SDRAM standard includes features designed to improve reliability and security and enhance performance in a range of applications from high-performance servers to emerging technologies such as AI and ML. JESD79-5C is available for download from the JEDEC website.

It introduces a solution to improve DRAM data integrity called Per-Row Activation Counting (PRAC). PRAC precisely counts DRAM activations on a wordline granularity. When PRAC-enabled DRAM detects an excessive number of activations, it alerts the system to pause traffic and to designate time for mitigative measures. These interrelated actions underpin PRAC’s ability to provide a fundamentally accurate and predictable approach for addressing data integrity challenges through close coordination between the DRAM and the system.

Additional features offered in JESD79-5C DDR5 include:

Expansion of timing parameters definition from 6,800 to 8,800Mb/s
Inclusion of DRAM core timings and Tx/Rx AC timings extended up to 8,800Mb/s, compared to the previous version which supported only up to 6400 timing parameters and partial pieces up to 7200 DRAM core timings
Introduction of Self-Refresh Exit Clock Sync for I/O Training Optimization
Incorporation of DDP (Dual-Die Package) timings
Deprecation of PASR (Partial Array Self Refresh) to address security concerns

“I’m delighted to highlight the collaborative efforts of JEDEC’s JC-42 Committee for Solid State Memory to advance the DDR5 standard,” said Mian Quddus, JEDEC board of directors chairman. “Groundbreaking new features in JESD79-5C are intended to support ever-evolving industry demands for security, reliability and performance in a wide range of applications.”

“The JC-42 Committee is pleased to unveil PRAC, a comprehensive solution to help ensure DRAM data integrity, as an integral component of the DDR5 update. Work is underway to incorporate this feature into other DRAM product families within JEDEC,” noted Christopher Cox, JC-42 committee chair.