JEDEC JESD79 DDR SDRAM Standard

The JEDEC Standard JESD79 is a specification that defines the details of DDR SDRAM memory integrated circuits.


SDRAM Memory Tutorial Includes:
What is SDRAM memory     SDRAM architecture     SDRAM timing & control     DDR / DDR1 SDRAM     DDR2 SDRAM     DDR3 SDRAM     DDR4 SDRAM     JEDEC 79 Standard    

Memory types:   Memory types & technologies     DRAM     EEPROM     Flash     FRAM     MRAM     Phase change memory     SDRAM     SRAM    


The ability to use an SDRAM memory from any manufacturer it is necessary to have a common standard. To enable SDRAM DDR memories to be sourced from any supplier, a standard has been drawn up by, JEDEC, Joint Electron Device Engineering Council.

In this way it is possible to equipment manufacturers to source their components from any manufacturer of DDR SDRAM knowing that they are interchangeable. This is important when it is necessary to be able to state a second source on any components.

This can only be done if they conform to the same standard. Accordingly JEDEC developed their standard JESD79 to enable manufacturers of DDR SDRAM to produce product that was interchangeable.

JEDEC DDR SDRAM Standard JESD79 outline

The JEDEC DDR SDRAM specification or standard defines all required aspects of 64Mb through 1Gb DDR SDRAMs with X4/X8/X16 data interfaces. It includes a whole variety of elements including features, functionality, ac and dc parametrics, packages and pin assignments.

The DDR SDRAM specification is expanded will be expanded to formally apply to x32 devices, and higher density devices as well.

The aim of the JEDEC JESD79 DDR SDRAM Standard is to define the minimum set of requirements for 64Mb through 1Gb, X4/X8/X16 JEDEC compliant DDR SDRAMs.

This enables system designs based on the required aspects of the specification to be supported by all DDR SDRAM vendors providing JEDEC compliant devices.

JEDEC DDR SDRAM Standard JESD79 releases

As with any stanard, the JEDEC 79 standard has undergone a number of updates and revisions to enable it to meet the current requirements, keeping pace with technology:


JEDEC JESD79 Releases
JESD79 Release Verson DDR Type
JESD-1 (June 2000) DDR
JESD-2 DDR2
JESD-3 DDR3
JESD-4 DDR4
JESD-5  

Updates of the individual JESD standars are of the form JESD-XV, where X is a numeric indicating the standard version or type, and V indicates the version of that standard, e.g. JESD-3F is version F of JESD-3 for DDR3 memories.

More Electronic Components:
Batteries     Capacitors     Connectors     Diodes     FET     Inductors     Memory types     Phototransistor     Quartz crystals     Relays     Resistors     RF connectors     Switches     Surface mount technology     Thyristor     Transformers     Transistor     Unijunction     Valves / Tubes    
    Return to Components menu . . .