The is the definitive technical standard for DDR4 SDRAM , published by JEDEC (the Joint Electron Device Engineering Council). This specification outlines the minimum requirements for DDR4 memory devices, ensuring they are interchangeable and reliable across different manufacturers and hardware platforms. Core Specifications and Features
It supports various data bus widths, specifically x4, x8, and x16 . jesd79-4d pdf
The document specifies package pinouts, ball/signal assignments, and electrical (AC and DC) characteristics. Evolution and Revisions The is the definitive technical standard for DDR4
First published in September 2012, the standard has seen multiple updates (4A, 4B, 4C) to incorporate new features like 3D Stacked SDRAM (Addendum No. 1) and refined timing parameters. JESD79-4D introduced enhancements like the Pseudo Open Drain
JESD79-4D introduced enhancements like the Pseudo Open Drain (POD) interface and bank groups . Bank groups allow for faster data access by enabling simultaneous operations across different sets of banks. JESD79-4D vs. Later Generations
JESD79-4D serves as the authoritative guide for engineers and manufacturers, covering a broad range of technical parameters: