JEDEC memory standards

The JEDEC memory standards are the specifications for semiconductor memory circuits and similar storage devices promulgated by the Joint Electron Device Engineering Council (JEDEC) Solid State Technology Association, a semiconductor trade and engineering standardization organization.

JEDEC Standard 100B.01 specifies common terms, units, and other definitions in use in the semiconductor industry. JESC21-C specifies semiconductor memories from the 256 bit static RAM to the latest DDR3 SDRAM modules. In August 2011, JEDEC announced that its DDR4 standard was expected to be published in mid-2012.

The Joint Electron Device Engineering Council characterizes its standardization efforts as follows:

JEDEC standards and publications are designed to serve the public interest through eliminating misunderstandings between manufacturers and purchasers, facilitating interchangeability and improvement of products, and assisting the purchaser in selecting and obtaining with minimum delay the proper product for use by those other than JEDEC members, whether the standard is to be used either domestically or internationally.

JEDEC Standard 100B.01 is entitled Terms, Definitions, and Letter Symbols for Microcomputers, Microprocessors, and Memory Integrated Circuits. The purpose of the standard is to promote the uniform use of symbols, abbreviations, terms, and definitions throughout the semiconductor industry.

The specification defines the two common units of information:

The specification contains definitions of the commonly used prefixes kilo, mega, and giga usually combined with the units byte and bit to designate multiples of the units.

The specification cites three prefixes as follows:

The specification notes that these prefixes are included in the document only to reflect common usage. It refers to the IEEE/ASTM SI 10-1997 standard as stating, that "this practice frequently leads to confusion and is deprecated". However the JEDEC specification does not explicitly deprecate the common usage. The document further refers to the description of the IEC binary prefixes in Amendment 2 of IEC 60027-2, "Letter symbols to be used in electrical technology", for an alternate system of prefixes and includes a table of the IEC prefixes in the note. However the JEDEC specification does not explicitly include the IEC prefixes in the list of general terms and definitions.

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