. While JEDEC members have free access, non-members may be required to register for a free account or pay a fee for certain standards. Purchasing
: Revision 4D includes specific text color-coding for engineering review: indicates new updates, while represents the established standard. 吴川斌的博客 Why It Matters jesd79-4d pdf
If you are designing a new DDR4 product, use -D. If you have a mature -C design, the changes are low-risk but worth back-annotating for validation. jesd79-4d pdf