MultiMediaCard: Difference between revisions

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→Embedded MMC {{anchor|eMMC}}: Higher capacity variants write faster.
 
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{{distinguish|SD card}}
{{distinguish|SD card}}
{{Infobox media
{{Infobox media
| logo          =  
| logo          =
| image        = 15-04-29-MMC-Karte-RalfR-dscf4734-d.jpg
| image        = 15-04-29-MMC-Karte-RalfR-dscf4734-d.jpg
| caption      = 32 [[Megabyte|MB]] MMCplus card
| caption      = 32 [[Megabyte|MB]] MMCplus card
| type          = [[Memory card]]
| type          = [[Memory card]]
| capacity      = Up to 512 GB
| capacity      = Up to 512 GB
| read          =  
| read          =
| write        =  
| write        =
| standard      =  
| standard      =
| owner        = [[JEDEC]]
| owner        = [[JEDEC]]
| use          = Portable devices
| use          = Portable devices
| dimensions    = Standard: 32 × 24 × 1.4 mm
| dimensions    = {{cvt|32|xx|24|xx|1.4|mm|1}}
| weight        = Standard: ~2.0 g
| weight        = {{cvt|2|g}}
| extended from =
| extended from =
| extended to  = [[Secure Digital]] (SD)
| extended to  = [[Secure Digital]] (SD)
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{{Memory types}}
{{Memory types}}


'''MultiMediaCard''', officially abbreviated as '''MMC''', is a [[memory card]] standard used for [[solid-state storage]]. Unveiled in 1997 by [[SanDisk]] and [[Siemens]],<ref>{{cite book |url=https://www.tomshardware.com/reviews/flash-removable-storage-ssd-drive,3626-3.html |title=Upgrading And Repairing PCs 21st Edition |publisher=Que Publishing |author=Scott Mueller |date=3 August 2014 |isbn=978-0789750006 }}</ref> MMC is based on a surface-contact low-pin-count serial interface using a single memory stack substrate assembly, and is therefore much smaller than earlier systems based on high-pin-count parallel interfaces using traditional surface-mount assembly such as [[CompactFlash]]. Both products were initially introduced using SanDisk [[NOR flash|NOR-based flash]] technology.
'''MultiMediaCard''' ('''MMC''') is a [[memory card]] standard used for [[solid-state storage]], originally introduced in 1997 by [[SanDisk]], [[Siemens]], and [[Nokia]]. Designed as a compact, low-pin-count, postage‑stamp‑sized card alternative to earlier storage solutions, MMC uses a serial interface and a single memory stack assembly, making it smaller and simpler than high-pin-count, parallel-interface cards such as [[CompactFlash]], which was previously developed by SanDisk.


MMC is about the size of a postage stamp: 32&nbsp;mm&nbsp;× 24&nbsp;mm&nbsp;× 1.4&nbsp;mm.  MMC originally used a 1-[[bit]] [[serial interface]], but newer versions{{when|date=March 2018}} of the specification allow transfers of 4 or 8 bits at a time. MMC can be used in many devices that can use [[Secure Digital]] (SD) cards. MMCs may be available in sizes up to 16 [[gigabyte]]s (GB).
It has since evolved into several variants, including the widely used [[SD card]] and the eMMC ([[embedded system|embedded]] MMC) which is soldered directly onto a device's circuit board. While removable MMC cards have largely been supplanted by SD cards, eMMC remains common in low-cost smartphones, tablets, and budget laptops due to its compact size and affordability, despite being slower and less upgradeable than modern solid-state drives


They are used in almost every context in which [[memory card]]s are used, like [[mobile phone|cellular phone]]s, digital audio players, [[Digital camera|digital cameras]], and [[Personal digital assistant|PDA]]s. Typically, an MMC operates as a storage medium for devices, in a form that can easily be removed for access by a [[Personal computer|PC]] via a connected MMC reader.
== History ==
[[File:MMC card vs SDHC card undersides angle.jpg|thumb|Undersides of an MMC (left) and SD card (right) showing the differences between the two formats]]In 1994, SanDisk introduced the CompactFlash format, one of the first commercially successful flash memory card types. CompactFlash outpaced competing formats of the time, including the [[Miniature Card]] and [[SmartMedia]]. However, the late 1990s saw a proliferation of proprietary memory card formats, such as [[Memory Stick]] from [[Sony]] and the [[xD-Picture Card]] developed by [[Olympus Corporation|Olympus]] and [[Fujifilm]], leading to a fragmented and incompatible landscape for removable storage.<ref name="shendar2022">{{Cite web |last=Shendar |first=Ronni |date=September 29, 2022 |title=The Invention of the SD Card: When Tiny Storage Met Tech Giants |url=https://blog.westerndigital.com/invention-sd-card/ |access-date=June 19, 2025 |website=[[Western Digital]]}}</ref>
 
In response to this fragmentation, SanDisk partnered with [[Siemens]] and [[Nokia]] in 1996 to create a universal, compact memory card standard. The resulting format, known as the MultiMediaCard (MMC), was officially introduced in 1997.<ref name="shendar2022" /> MMC was designed to be significantly smaller than CompactFlash, with a postage stamp-sized form factor, and to use just seven flat electrical contacts and a simplified serial interface, reducing complexity in host devices. The MultiMediaCard Association (MMCA), was founded in 1998 by 14 companies to promote adoption of the format.<ref>{{Cite web |title=MMCA: Association Backgrounder |url=http://mmca.org/press/backgrounder.html |archive-url=https://web.archive.org/web/20050208222932/http://mmca.org/press/backgrounder.html |archive-date=February 8, 2005 |access-date=June 23, 2025 |website=mmca.org}}</ref>
 
Compared to the physically larger CompactFlash, which relied on 50-pin parallel interfaces and traditional surface-mount assembly, MMC offered a more streamlined and mobile-friendly design, which the MMCA hoped would make it attractive for use in portable consumer electronics such as digital cameras, handheld devices, and mobile phones.
 
Despite its technical advantages, MMC adoption was limited. Even Nokia, one of the original backers, was slow to integrate MMC into its popular handsets.<ref name="shendar2022" /> In an effort to boost adoption, the MMCA introduced revised specifications between 2004 and 2007, including reduced power consumption, support for smaller form factors, and increased storage capacities. However, these updates had limited market impact.
 
MMC technology served as the foundation for the development of the [[Secure Digital]] (SD) card standard. Introduced in 1999 by SanDisk, [[Panasonic]], and [[Toshiba]], SD was based on the MMC electrical interface but added digital rights management (DRM), more durable casing, and a mechanical write-protect switch. These enhancements, along with broad manufacturer support, led SD to surpass MMC in popularity. Many early SD-compatible devices also supported MMC cards.<ref>{{Cite web |date=August 25, 1999 |title=Three Giants to develop new "Secure Memory Card" |url=https://www.dpreview.com/articles/6861681955/newmemory |access-date=June 19, 2025 |website=Digital Photography Review}}</ref>
 
MMC's most enduring legacy came in the form of its embedded variant, eMMC (embedded MultiMediaCard). First introduced by the [[JEDEC Solid State Technology Association]] in 2006 with version 4.0 of the standard, eMMC adapted the MMC architecture for non-removable storage integrated directly onto a device’s motherboard.<ref name="TechTarget" /> The eMMC format proved especially successful in smartphones, tablets, Chromebooks, and other low-cost computing devices due to its low cost,<ref name="eMMC Chips" /> compact size, and adequate performance for basic tasks.<ref name="WindowsCentral2024" />


'''eMMC''' ([[embedded system|embedded]] MMC) is a small MMC chip used as [[Embedded system|embedded]] [[non-volatile memory]] that is normally soldered on [[printed circuit boards]], though pluggable eMMC modules are used on some devices (e.g. [[Orange Pi]] and [[ODROID]]).<ref>{{Cite web |last=Hunt |first=Cale |date=2023-02-06 |title=eMMC vs. SSD storage: What's the difference? |url=https://www.windowscentral.com/emmc-vs-ssd |url-status=live |archive-url=https://web.archive.org/web/20240218153058/https://www.windowscentral.com/emmc-vs-ssd |archive-date=2024-02-18 |access-date=2024-03-04 |website=Windows Central |language=en}}</ref><ref>{{Cite web |last=Ree |first=Brian |title=eMMC Memory Modules: A Simple Guide |url=https://magazine.odroid.com/article/emmc-memory-modules-a-simple-guide/ |url-status=live |archive-url=https://web.archive.org/web/20230921195144/https://magazine.odroid.com/article/emmc-memory-modules-a-simple-guide/ |archive-date=2023-09-21 |access-date=2024-03-04 |website=ODROID Magazine |language=en-US}}</ref><ref>{{Cite web |title=Orange Pi 32GB/64GB/256GB eMMC Module |url=http://www.orangepi.org/html/hardWare/computerAndMicrocontrollers/details/Orange-Pi-emmc.html |url-status=live |archive-url=https://web.archive.org/web/20240206002753/http://www.orangepi.org/html/hardWare/computerAndMicrocontrollers/details/Orange-Pi-emmc.html |archive-date=2024-02-06 |access-date=2024-03-04 |website=www.orangepi.org}}</ref>
On September 23, 2008, the MMCA formally transferred control of the MMC specification to JEDEC.<ref>{{Cite press release |title=MultiMediaCard Association Merges with JEDEC |date=September 23, 2008 |url=https://www.jedec.org/news/pressreleases/multimediacard-association-merges-jedec |access-date=October 29, 2022 |website=JEDEC}}</ref> While JEDEC continued to update the eMMC standard, removable MMC cards saw little further development.<ref name="WindowsCentral2024" /><ref name="JEDEC 2019" /> {{As of|2025}}, the format has largely faded from use. eMMC itself is gradually being supplanted in performance-oriented applications by newer technologies such as [[Universal Flash Storage]] (UFS) and [[Solid-state drive|solid-state drives]] (SSDs), although it remains in use in budget-conscious and embedded devices.  


== History ==
== MMC card variants ==
{{multiple image
{{multiple image
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  | header =
  | image1 = Four MMC cards front.jpg
  | image1 = Four MMC cards front.jpg
  | alt1 = Front of four different MMC cards: MMC, RS-MMC, MMCplus, MMCmobile, and metal extender
  | alt1 = Front of four different MMC cards: MMC, RS{{nbhyph}}MMC, MMCplus, MMCmobile, and metal extender
  | caption1 = Top of four types of MMC cards (clockwise from left): MMC, RS-MMC, MMCplus, MMCmobile, metal extender
  | caption1 = Top of four types of MMC cards (clockwise from left): MMC, RS-MMC, MMCplus, MMCmobile, metal extender
  | image2 = 01fourcardsrev.curve.jpg
  | image2 = 01fourcardsrev.curve.jpg
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  | caption2 = Bottom of the same four cards
  | caption2 = Bottom of the same four cards
}}
}}
The latest version of the eMMC standard ([https://www.jedec.org/standards-documents/docs/jesd84-b51 JESD84-B51]) by JEDEC is version 5.1A, released January 2019, with speeds (250&nbsp;MB/s read, 125&nbsp;MB/s write) rivaling discrete [[Serial ATA|SATA]]-based SSDs (500&nbsp;MB/s).<ref>{{cite web |title=e.MMC v5.1 |url=http://www.jedec.org/standards-documents/technology-focus-areas/flash-memory-ssds-ufs-emmc/e-mmc |access-date=2015-08-21 |publisher=JEDEC}}</ref>
[[File:MMC card vs SDHC card undersides angle.jpg|thumb|right|Undersides of an MMC (left) and SD card (right) showing the differences between the two formats]]
As of 23 September 2008, the [[MultimediaCard Association]] (MMCA) turned over all MMC specifications to the [[JEDEC|JEDEC organization]] including embedded MMC (eMMC), SecureMMC, and miCARD assets.<ref>{{Cite web |title=MultiMediaCard Association Merges with JEDEC {{!}} JEDEC |url=https://www.jedec.org/news/pressreleases/multimediacard-association-merges-jedec |access-date=2022-10-29 |website=www.jedec.org}}</ref> JEDEC is an organization devoted to standards for the solid-state industry.
The latest eMMC specifications can be requested from JEDEC, free-of-charge for JEDEC members.<ref>{{Cite web |title=Standards & Documents Search {{!}} JEDEC |url=https://www.jedec.org/document_search?search_api_views_fulltext=jesd84-b51 |access-date=2022-10-29 |website=www.jedec.org}}</ref> Older versions of the standard are freely available, but some optional enhancements to the standard such as MiCard and SecureMMC specifications, must be purchased separately.
While there is no royalty charged for devices to host an MMC or eMMC, a royalty may be necessary in order to manufacture the cards themselves.
A highly detailed datasheet<ref>{{cite web |url=http://html.alldatasheet.com/html-pdf/141187/SAMSUNG/MC2GH512NMCA-2SA00/305/1/MC2GH512NMCA-2SA00.html |title=MC2GH512NMCA-2SA00 datasheet(1/102 Pages) SAMSUNG &#124; SAMSUNG MultiMediaCard |website=Html.AllDatasheet.com |date=2005-09-22 |access-date=2013-11-13}}</ref> that contains essential information for writing an MMC host driver is available online.
== Variants ==


=== RS-MMC ===
=== RS-MMC ===
 
'''Reduced Size MultiMediaCard''' ('''RS{{nbhyph}}MMC'''), introduced in 2002,<ref>{{Cite web |date=November 11, 2002 |title=Reduced Size MultiMediaCard Standard Approved by MMCA |url=http://mmca.org/press/RS-MMC-final.PDF |archive-url=https://web.archive.org/web/20050208220807/http://mmca.org/press/RS-MMC-final.PDF |archive-date=February 8, 2005 |access-date=June 23, 2025 |website=mmca.org}}</ref> is a smaller variant of MMC, measuring approximately {{Convert|24|x|18|x|1.4|mm}}, about half the height of a standard MMC.<ref name=":0">{{Cite web |last=Kolokowsky |first=Steve |date=July 3, 2006 |title=Untangle the web of removable storage |url=https://www.eetimes.com/untangle-the-web-of-removable-storage/ |access-date=June 23, 2025 |website=EE Times}}</ref> It uses a simple extender to work in standard MMC or SD slots and was available in capacities up to 2&nbsp;GB. Some manufacturers, including Nokia and Siemens, briefly adopted RS{{nbhyph}}MMC in their early [[Symbian]]-based smartphones and tablets.
In 2004, the '''Reduced-Size MultiMediaCard''' ('''RS-MMC''') was introduced as a smaller form factor of the MMC, with about half the size: 24&nbsp;mm&nbsp;× 18&nbsp;mm&nbsp;× 1.4&nbsp;mm. The RS-MMC uses a simple mechanical adapter to elongate the card so it can be used in any MMC (or SD) slot. RS-MMCs are currently available in sizes up to and including 2&nbsp;GB.
 
The modern continuation of an RS-MMC is commonly known as '''MiniDrive''' ('''MD-MMC'''). A MiniDrive is generally a [[microSD]] card adapter in the RS-MMC form factor. This allows a user to take advantage of the wider range of modern MMCs available<ref>TheMiniDrive.com, http://www.TheMiniDrive.com. Extracted 23 April 2014.</ref> to exceed the historic 2&nbsp;GB limitations of older chip technology.
 
Implementations of RS-MMCs include [[Nokia]] and [[Siemens cellular telephones|Siemens]], who used RS-MMC in their [[Series 60]] [[Symbian]] [[smartphone]]s, the [[Nokia 770 Internet Tablet]], and generations 65 and 75 (Siemens). However, since 2006, all of Nokia's new devices with card slots have used [[miniSD]] or [[microSD]] cards, with the company dropping support for the MMC standard in its products. While Siemens exited the mobile phone business completely in 2006, the company continues to use MMC for some [[Programmable logic controller|PLC]] storage leveraging MD-MMC advances.


=== DV-MMC ===
=== DV-MMC ===
'''Dual Voltage MMC''' ('''DV{{nbhyph}}MMC, also called the Low Voltage MMC''') supported 1.8&nbsp;V alongside the normal 3.3&nbsp;V operation to reduce power consumption in mobile devices. This variant was first proposed in 2001,<ref>{{Cite press release |title=MultiMediaCard Association Approves System Specification 3.1 |date=June 27, 2001 |url=http://www.mmca.org/press/press010627b.pdf |access-date=June 23, 2025 |archive-url=https://web.archive.org/web/20041020003713/http://www.mmca.org/press/press010627b.pdf |archive-date=October 20, 2004 |website=MultiMediaCard Association}}</ref> but wasn't widely available until 2004,<ref>{{Cite press release |title=Samsung Launches Dual Voltage Memory Card for Mobile Appliances |date=March 29, 2004 |url=http://www.mmca.org/news/Samsung-Dual-Voltage-MMC1.pdf |access-date=June 23, 2025 |archive-url=https://web.archive.org/web/20050305171455/http://www.mmca.org/news/Samsung-Dual-Voltage-MMC1.pdf |archive-date=March 5, 2005 |website=Samsung}}</ref> and was soon overtaken by the more capable MMCplus and MMCmobile formats.


The Dual-Voltage MultimediaCard ('''DV-MMC''') was one of the first changes in MMC.{{Citation needed|date=December 2022}} These cards can operate at 1.8&nbsp;V in addition to 3.3&nbsp;V. Running at lower voltages reduces the card's energy consumption, which is important in mobile devices. However, simple dual-voltage parts quickly went out of production in favor of MMCplus and MMCmobile, which offer capabilities in addition to dual-voltage capability.
=== MMCplus, MMCmobile and MMCmicro ===
 
=== MMCplus and MMCmobile ===
[[File:MMCplus and MMCmobile logo (recreated).png|thumb|Recreations of the MMCplus and MMCmobile logos]]
 
The version 4.x of the MMC standard, introduced in 2005, introduced two significant changes to compete against SD cards: (1) the ability to run at higher speeds (26&nbsp;MHz and 52&nbsp;MHz) than the original MMC (20&nbsp;MHz) or SD (25&nbsp;MHz, 50&nbsp;MHz), and (2) a four- or eight-bit-wide [[Bus (computing)|data bus]].
 
Version 4.x full-size cards and reduced-size cards can be marketed as '''MMCplus''' and '''MMCmobile''', respectively.
 
Version 4.x cards are fully backward compatible with existing readers but require updated hardware and software to use their new capabilities. Even though the four-bit-wide bus and high-speed modes of operation are deliberately electrically compatible with SD, the initialization protocol is different, so firmware and software updates are required to use these features in an SD reader.
 
=== MMCmicro ===
[[File:Mmc-micro.PNG|thumb|MMCmicro]]
[[File:Mmc-micro.PNG|thumb|MMCmicro]]
The '''MMCplus''' and '''MMCmobile''' formats were introduced in 2004 and the '''MMCmicro''' format in 2005 as part of version 4 of the MMC specification with several enhancements to improve performance and better compete with SD cards.<ref>{{Cite press release |title=MultiMediaCard Specification Version 4.0 is Released |date=February 2, 2004 |url=http://www.mmca.org/press/MMCA-SpecV-4.pdf |access-date=June 23, 2025 |url-status=dead |archive-url=https://web.archive.org/web/20050305192601/http://www.mmca.org/press/MMCA-SpecV-4.pdf |archive-date=March 5, 2005 |website=MultiMediaCard Association}}</ref><ref>{{Cite press release |title=MultiMediaCard Association Announces MMCplus and MMCmobile Cards |date=September 20, 2004 |url=http://www.mmca.org/press/NewBranding.pdf |access-date=June 23, 2025 |archive-url=https://web.archive.org/web/20050305171127/http://www.mmca.org/press/NewBranding.pdf |archive-date=March 5, 2005 |website=MultiMediaCard Association}}</ref><ref>{{Cite press release |title=The MultiMediaCard Association Finalizes MMCmicro Card Specification |date=July 21, 2005 |url=http://www.mmca.org/press/MMCmicroFinal.pdf |access-date=June 23, 2025 |archive-url=https://web.archive.org/web/20061010173014/http://www.mmca.org/press/MMCmicroFinal.pdf |archive-date=October 10, 2006 |website=MultiMediaCard Association}}</ref> These enhancements included support for higher clock speeds (26&nbsp;MHz and 52&nbsp;MHz alongside the normal 20&nbsp;MHz) and wider data buses (8{{nbhyph}}bit alongside the previous 1- and 4{{nbhyph}}bit), which combined to enable a 52 Mbit/s transfer rate, alongside dual-voltage support (1.8&nbsp;V and 3.3&nbsp;V) carried over from DV‑MMC.<ref name=":0" /> 


'''MMCmicro''' is a smaller version of MMC. With dimensions of 14&nbsp;mm&nbsp;× 12&nbsp;mm&nbsp;× 1.1&nbsp;mm, it is smaller and thinner than RS-MMC. Like MMCmobile, MMCmicro allows dual voltage, is backward compatible with MMC, and can be used in full-size MMC and SD slots with a mechanical adapter. MMCmicro cards have the high-speed and four-bit-bus features of the 4.x spec, but not the eight-bit bus, due to the absence of the extra pins.<ref>{{cite web|url=http://www.samsung.com/Products/Semiconductor/FlashCard/MMC/micro_mmc.htm |title=Samsung Semiconductor Global Official Website |language=ru |publisher=Samsung.com |access-date=2013-11-13}}</ref>
The full‑size enhanced format was marketed as MMCplus, while its smaller counterpart, matching the size of RS-MMC, was known as MMCmobile. Cards have 13 flat electrical contacts to support 8{{nbhyph}}bit data buses.<ref name=":0" /> Both formats maintained backward compatibility with devices with standard MMC readers, though without support for some of their advanced features.<ref>{{Cite web |date=2005 |title=MultiMediaCard Brochure |url=http://www.mmca.org/press/mmca_brochure_120204-final-lores.pdf |archive-url=https://web.archive.org/web/20050408190720/http://www.mmca.org/press/mmca_brochure_120204-final-lores.pdf |archive-date=April 8, 2005 |access-date=June 23, 2025 |website=MultiMediaCard Association}}</ref>


This variant was formerly known as ''S-card'' when introduced by [[Samsung]] on 13 December 2004. It was later adapted and introduced in 2005 by the MultiMediaCard Association (MMCA) as the third form factor memory card in the ''MultiMediaCard'' family.<ref>allmemorycards.com, ''[http://www.allmemorycards.com/mmc-micro.htm MMCmicro]''. Extracted 22 April 2006.</ref>
The MMCmicro format featured a compact {{Convert|14|x|12|x|1.1|mm}} form factor to compete with microSD cards. It supported dual-voltage and high-speed 4‑bit operation, though it lacked the pins required for an 8‑bit bus. MMCmicro cards could be used with an adapter for use in full-size MMC slots.<ref name=":0" />
 
MMCmicro appears very similar to [[microSD]], but the two formats are not physically compatible and have incompatible pinouts.


=== MiCard ===
=== MiCard ===
The '''miCARD''' '''(Multiple Interface Card)''' was a high‑capacity MMC variant proposed in 2007 that could be plugged directly into a USB port eliminating the need for dedicated card slots or separate card readers and could be used in standard MMC/SD slots via an adapter.<ref>{{Cite press release |title=MultiMediaCard Association Announces Specification for Multiple-Interface Memory Cards |date=May 31, 2007 |url=http://www.mmca.org/home/MMCA_MiCard_052907_FINAL.pdf |access-date=June 23, 2025 |archive-url=https://web.archive.org/web/20070706114800/http://www.mmca.org/home/MMCA_MiCard_052907_FINAL.pdf |archive-date=July 6, 2007 |website=MultiMediaCard Association}}</ref> The card would have been slightly smaller than a RS-MMC/MMCmobile card, but larger than MMCmicro at {{Convert|21|x|12|x|1.95|mm}}.<ref>{{Cite web |last=Melanson |first=Donald |date=May 31, 2007 |title=MMCA announces MiCard specification for MMC / USB combo cards |url=https://www.engadget.com/2007-05-31-mmca-announces-micard-specification-for-mmc-usb-combo-cards.html |access-date=June 23, 2025 |website=Engadget |language=en-US}}</ref> Despite backing from several Taiwanese companies, MiCard never reached mass production.


The '''MiCard''' is a backward-compatible extension of the MMC standard with a theoretical maximum size of 2048&nbsp;GB (2 terabytes) announced on 2 June 2007. The card is composed of two detachable parts, much like a microSD card with an SD adapter. The small memory card fits directly in a USB port and has MMC-compatible electrical contacts. With an included electromechanical adapter, it can also fit in traditional MMC and SD card readers. To date, only one manufacturer (Pretec) has produced cards in this format.<ref name=micard>{{ cite web | title = Pretec Announces S-Diamond, 1st in the World to Implement miCARD Standard | url = http://www.businesswire.com/portal/site/google/index.jsp?ndmViewId=news_view&newsId=20070604006489&newsLang=en | access-date = 21 January 2010 }}</ref>
== Embedded MMC {{anchor|eMMC}} ==
 
[[File:Samsung Galaxy Tab 2 10.1 - Samsung KLMAG2GE4A-A002-3955.jpg|thumb|eMMC chip inside the [[Samsung Galaxy Tab 2 10.1]]]]
The MiCard was developed by the [[Industrial Technology Research Institute]] in [[Taiwan]]. At the time of the announcement, twelve Taiwanese companies (including [[ADATA]] Technology, [[Asustek]], [[BenQ]], [[Carry Computer Eng. Co.]], [[C-One Technology]], [[DBTel]], [[Power Digital Card Co.]], and [[RiCHIP]]) had signed on to manufacture the new memory card. However, as of June 2011, none of the listed companies had released any such cards, nor had any further announcements been made about plans for the format.


The card was announced to be available starting in the third quarter of 2007. It was expected to save the 12 Taiwanese companies who planned to manufacture the product and related hardware up to US$40 million in licensing fees, which presumably would otherwise be paid to owners of competing flash memory formats. The initial card was to have a capacity of 8&nbsp;GB, while the standard would allow sizes up to 2048&nbsp;GB. It was stated to have data transfer speeds of 480&nbsp;[[Mbit/s]] (60&nbsp;[[Mbyte/s]]), with plans to increase data over time.
The '''embedded MultiMediaCard''' ('''eMMC''', officially branded as ''e''•MMC) is a type of internal storage that integrates [[NAND flash]] memory,<ref>{{Cite web |date=September 6, 2016 |title=NAND and eMMC: All You Need to Know About Flash Memory |url=https://www.makeuseof.com/tag/nand-emmc-need-know-flash-memory/}}</ref> a buffer, and a controller into a single [[ball grid array]] (BGA) package. Unlike other forms of removable card-based MMC storage, eMMC is permanently soldered onto a device's [[printed circuit board]] (PCB) and is not user-removable or upgradeable. The onboard controller manages tasks such as error correction and data handling, reducing the workload on the device's main processor. eMMC chips use an 8-bit parallel interface and are available in various physical sizes and storage capacities.<ref>{{Cite web |title=Flash Memory Form Factors |url=https://www.hyperstone.com/en/Registration-Hyperstone-1125.html |url-access=registration |access-date=April 19, 2018 |series=The Fundamentals of Reliable Flash Storage |publisher=Hyperstone GmbH}}</ref><ref>{{Cite web |title=What is eMMC Memory – software support – Reliance Nitro |url=http://www.datalight.com/solutions/technologies/emmc/what-is-emmc |website=datalight.com}}</ref>


=== eMMC ===
The eMMC standard was first introduced by the JEDEC Solid State Technology Association in 2006 with version 4.0, which adapted the original card-based MMC specification for embedded (non-removable) and mobile applications.<ref name="TechTarget">{{Cite web |title=What is eMMC? (embedded MultiMediaCard) |url=https://www.techtarget.com/searchstorage/definition/eMMC-embedded-MultiMediaCard |access-date=June 22, 2025 |website=TechTarget |publisher=SearchStorage}}</ref> Between 2007 and 2012, the version 4 standard was revised multiple times to improve performance and introduce features such as [[Secure Erase|secure erase]] and on-system [[Patch (computing)|firmware updates]]. Version 5.0, released in 2013, introduced the HS400 interface mode, enabling theoretical data transfer speeds of up to 400&nbsp;MB/s, along with enhancements to reliability and boot performance. This was followed by version 5.1 in 2015, which added [[Command queue|command queuing]] and further reliability improvements.<ref name="WindowsCentral2024">{{Cite web |last=Hunt |first=Cale |date=October 2, 2024 |title=eMMC vs. SSD storage: What was the difference, and does it matter now? |url=https://www.windowscentral.com/hardware/emmc-vs-ssd-storage-what-was-the-difference-and-does-it-matter-now |website=Windows Central}}</ref> The most recent update, version 5.1A, was released in 2019 and included minor refinements to the standard.<ref name="JEDEC 2019">{{Cite web |date=February 27, 2019 |title=JEDEC Publishes New UFS, e.MMC, and SPI NOR Flash Standards |url=https://www.jedec.org/news/pressreleases/jedec-publishes-new-ufs-emmc-and-spi-nor-flash-standards |access-date=June 22, 2025 |website=JEDEC}}</ref>
[[File:Samsung Galaxy Tab 2 10.1 - Samsung KLMAG2GE4A-A002-3955.jpg|thumb|eMMC KLMAG2GE4A-A002 inside the [[Samsung Galaxy Tab 2 10.1]]]]


The currently implemented '''embedded MMC'''<ref>{{cite web |title=What is eMMC Memory – software support – Reliance Nitro |url=http://www.datalight.com/solutions/technologies/emmc/what-is-emmc |website=datalight.com}}</ref> ('''eMMC''' or '''{{notatypo|e.MMC}}''') architecture puts the MMC components (flash memory, buffer and controller) into a small [[ball grid array]] (BGA) IC package for use in circuit boards as an embedded non-volatile memory system. This is noticeably different from other versions of MMC as this is not a user-removable card, but rather a permanent attachment to the [[printed circuit board]] (PCB). Therefore, in the event of an issue with either the memory or its controller, the eMMC would need to be replaced or repaired. In eMMC, the host system simply reads and writes data to and from the [[Logical block addressing|logical block addresses]]. The eMMC controller hardware and firmware lifts the burden on the host system by performing error correction and data management. eMMC exists in 100, 153, and 169 ball packages and is based on an 8-bit parallel interface.<ref>{{cite web |url=https://www.hyperstone.com/en/Registration-Hyperstone-1125.html |url-access=registration |title=Flash Memory Form Factors |author=<!--Not stated--> |series=The Fundamentals of Reliable Flash Storage |publisher=Hyperstone GmbH |access-date=19 April 2018}}</ref>
eMMC became widely used as the primary storage medium in early [[smartphone]]s, and later in low-cost [[laptop computer]]s, [[Chromebook]]s, [[tablet computer]]s, and other compact computing devices. While it was gradually supplanted in higher-performance devices by alternatives such as Universal Flash Storage (UFS) in smartphones and solid-state drives (SSDs) in computers, eMMC continued to be used in entry-level products due to its low cost,<ref name="eMMC Chips">{{Cite web |title=eMMC Chips |url=https://www.mouser.com/c/semiconductors/memory-ics/emmc/?sort=pricing}}</ref> compact form factor, low power consumption, and adequate performance for everyday tasks such as web browsing, email, and video streaming.<ref name="WindowsCentral2024" />


Almost all mobile phones and tablets used this form of flash for main storage until 2016, when [[Universal Flash Storage]] (UFS) started to take control of the market. However, as of 2023, eMMC is still used in many consumer applications, including lower-end smartphones, such that [[Kioxia]] has introduced new 64&nbsp;GB and 128&nbsp;GB eMMC 5.1 modules based on modern [[3D NAND]] flash scheduled for mass production in 2024.<ref>{{Cite web |date=2023-09-27 |title=KIOXIA Introduces Next Generation e-MMC Ver. 5.1-Compliant Embedded Flash Memory Products |url=https://www.businesswire.com/news/home/20230927535891/en/KIOXIA-Introduces-Next-Generation-e-MMC-Ver.-5.1-Compliant-Embedded-Flash-Memory-Products |access-date=2023-09-28 |website=www.businesswire.com |language=en}}</ref><ref>{{Cite web |last=Shilov |first=Anton |title=eMMC Destined to Live a Bit Longer: KIOXIA Releases New Generation of eMMC Modules |url=https://www.anandtech.com/show/21074/emmc-to-live-a-bit-longer-kioxia-releases-new-emmc-products |access-date=2023-09-28 |website=www.anandtech.com}}</ref>  
While eMMC is faster and more power-efficient than traditional [[hard disk drive]]s, it is slower than most SSDs, especially those using [[NVMe]] over [[PCI Express]]. These speed limitations make it less suited for applications involving large files or intensive computing needs, such as gaming or video editing. Its lack of upgradeability also limits its appeal in more advanced systems, as users cannot replace or expand storage after purchase.<ref name="WindowsCentral2024" />


eMMC does not support the [[Serial Peripheral Interface|SPI-bus]] protocol and uses NAND flash.<ref>{{Cite web |date=6 September 2016 |title=NAND and eMMC: All You Need to Know About Flash Memory |url=https://www.makeuseof.com/tag/nand-emmc-need-know-flash-memory/}}</ref>
{| class="wikitable"
{| class="wikitable"
|+ eMMC versions
|+ eMMC versions<ref>{{Cite web |title=eMMC to UFS: How NAND Memory for Mobile Products Is Evolving |url=https://news.samsung.com/global/emmc-to-ufs-how-nand-memory-for-mobile-products-is-evolving |access-date=February 16, 2021 |website=Samsung |language=en}}</ref>
! Version
! Version
!Introduced
! Sequential read (MB/s)
! Sequential read (MB/s)
! Sequential write (MB/s)
! Sequential write (MB/s)
! Random read (IO/s)
! Random read ([[IOPS]])
! Random write (IO/s)
! Random write (IOPS)
! Clock frequency (MHz)
! Used in
|-
! 4.3
|
|
|
|
|
|
|-
|-
! 4.4
!4.3
|
|2007
|
|52<ref>{{Cite web |date=August 2013 |title=Samsung eMMC Brochure |url=https://download.semiconductor.samsung.com/resources/brochure/Samsung_eMMC_2013-0.pdf |archive-date= |access-date=28 June 2025 |website=Samsung}}</ref>
|
|48<ref>{{Cite web |date=November 2007 |title=eMMC/Card Product Standard |url=https://community.nxp.com/pwmxy87654/attachments/pwmxy87654/lpc/27039/1/JESD84-A43.pdf |access-date=28 June 2025 |website=JEDEC}}</ref>
|
|
|
|
|-
! 4.41
|
|
|
|
| 52<ref>{{Cite web |last1=Moon |first1=Yejin |date=2014-03-20 |orig-date=Presented in November 2011 |title=Q4.11: Introduction to eMMC |url=https://www.slideshare.net/linaroorg/intro-to-emmc}}</ref>
|
|
|-
|-
! 4.5
! 4.5
| 140<ref>{{Cite web |title=eMMC to UFS: How NAND Memory for Mobile Products Is Evolving |url=https://news.samsung.com/global/emmc-to-ufs-how-nand-memory-for-mobile-products-is-evolving |access-date=2021-02-16 |website=news.samsung.com |language=en}}</ref>
|2012
| 150
| 50
| 50
| 7000
| 7,000
| 2000
| 2,000
| 200
| [[Snapdragon 800]]
|-
|-
! 5.0
! 5.0
|2013
| 250
| 250
| 90
| 90
| 7000
| 7,000
| 13000
| 13,000
|
| Snapdragon 801
|-
|-
! 5.1
! 5.1
|2015
| 250
| 250
| 125
| 125
| 11000
| 11,000
| 13000
| 13,000
|
|}
| Snapdragon 820
|} <!--does repair mean replacing the emmc itself?-->


== Uses ==


Modern computers, both laptops and desktops, often have SD slots, which can additionally read MMCs if the operating system drivers can. Since the introduction of SD cards, few companies build MMC slots into their devices (an exception is some mobile devices like the [[Nokia 9300]] communicator in 2004, where the smaller size of the MMC is a benefit), but the slightly thinner, pin-compatible MMCs can be used in almost any device that can use SD cards if the software/firmware on the device is capable.
Higher capacity variants of eMMC reach higher writing speeds. While the reading speed of eMMC 5.0 remains constant at 250 MB/s throughout its storage options, a 64 GB eMMC 5.0 writes at up to 90 MB/s, more than six times faster than the 14 MB/s of the lowest storage option of 4 GB.<ref>[http://www.axeme.com.tw/comm/upfile/p_210623_06871.pdf Embedded Multimedia Card (eMMC 5.0 HS400) Specification (MLC)]: 2.1 System Performance</ref>
 
While few companies build MMC slots into devices {{as of | 2018 | lc = on}}, due to SD cards dominating the [[memory card]] market, the embedded MMC ({{notatypo|e.MMC}}) is still widely used in consumer electronics as a primary means of integrated storage and [[boot loader]] in portable devices. eMMC provides a low-cost<ref>{{Cite web |title=eMMC Chips |url=https://www.mouser.com/c/semiconductors/memory-ics/emmc/?sort=pricing}}</ref> flash-memory system with a built-in controller that can reside inside an [[Android (operating system)|Android]] or [[Microsoft Windows|Windows]] phone or in a low-cost PC and can appear to its host as a bootable device, in lieu of a more expensive form of solid-state storage, such as a traditional [[solid-state drive]].


== Similar formats ==
== Similar formats ==
In 2004, a group of companies—including [[Seagate Technology|Seagate]] and [[Hitachi]]—introduced an interface called [[CE-ATA]] for [[Small Form Factor committee|small form factor]] hard disk drives.<ref>{{Cite web |title=New Consumer Electronic Interface on Future Hard Drives |url=https://phys.org/news/2004-09-consumer-electronic-interface-future-hard.html |access-date=April 1, 2019 |website=Phys.org}}</ref> This interface was electrically and physically compatible with the MMC specification. However, support for further development of the standard ended in 2008.<ref>{{Cite web |title=Consumer Electronics ATA (CE-ATA) |url=https://www.techopedia.com/definition/26017/consumer-electronics-ata-ce-ata |access-date=April 1, 2019 |website=Technopedia}}</ref>


In 2004, a group of companies—including [[Seagate Technology|Seagate]] and [[Hitachi]]—introduced an interface called [[CE-ATA]] for [[Small Form Factor committee|small form factor]] hard disk drives.<ref>{{cite web |title=New Consumer Electronic Interface on Future Hard Drives |url=https://phys.org/news/2004-09-consumer-electronic-interface-future-hard.html |website=Phys.org |access-date=1 April 2019}}</ref> This interface was electrically and physically compatible with the MMC specification. However, support for further development of the standard ended in 2008.<ref>{{cite web |title=Consumer Electronics ATA (CE-ATA) |url=https://www.techopedia.com/definition/26017/consumer-electronics-ata-ce-ata |website=Technopedia |access-date=1 April 2019}}</ref>
The game card format used on the [[PlayStation Vita]] was found to be based on the MMC standard, but with a different pinout and support for custom initialization commands as well as copy protection.<ref name="vitadump">{{Cite web |date=August 25, 2016 |title=Playstation Vita Cartridge Dump explained |url=https://wololo.net/2016/08/25/playstation-vita-cartridge-dump-explained/ |access-date=July 29, 2022 |website=Wololo.net |language=en-US}}</ref>
 
The game card format used on the [[PlayStation Vita]] was found to be based on the MMC standard, but with a different pinout and support for custom initialization commands as well as copy protection.<ref name="vitadump">{{Cite web |last=wololo |date=2016-08-25 |title=Playstation Vita Cartridge Dump explained |url=https://wololo.net/2016/08/25/playstation-vita-cartridge-dump-explained/ |access-date=2022-07-29 |website=Wololo.net |language=en-US}}</ref>


== See also ==
== See also ==
* [[Comparison of memory cards]]
* [[Comparison of memory cards]]
* [[Universal Flash Storage]]


==References==
== References ==
{{refs}}
{{Reflist}}


== External links ==
== External links ==
{{commonscat|Multi Media Card}}
{{Commons category|Multi Media Card}}
 
* [https://www.jedec.org/standards-documents/technology-focus-areas/flash-memory-ssds-ufs-emmc/e-mmc eMMC Standard] – JEDEC.org
* [http://www.jedec.org/ JEDEC] – Solid State Technology Association
* {{webarchive|url=https://web.archive.org/web/20070126005916/https://www.sandisk.com/Assets/File/OEM/Manuals/ProdManRS-MMCv1.3.pdf|title=SanDisk MultiMediaCard and Reduced-Size MultiMediaCard Product Manual}}
* {{webarchive|url=https://web.archive.org/web/20071010143502/http://www.kingmaxdigi.com/product/MMC.pdf|title=KingMax Digital Inc. MMC Card Specification}}
* [http://www.hardwarebook.info/MMC MMC pinout (tech.)]
* [http://www.hardwarebook.info/MMCplus MMCplus pinout (tech.)]


{{Memory Cards}}
{{Memory Cards}}


{{Use dmy dates|date=August 2021}}
{{Use mdy dates|date=June 2025}}
[[Category:Open standards]]
[[Category:Open standards]]
[[Category:Sandisk]]
[[Category:Sandisk]]

Latest revision as of 11:51, 30 June 2025

Template:Short description Script error: No such module "Distinguish". Template:Infobox media Template:Memory types

MultiMediaCard (MMC) is a memory card standard used for solid-state storage, originally introduced in 1997 by SanDisk, Siemens, and Nokia. Designed as a compact, low-pin-count, postage‑stamp‑sized card alternative to earlier storage solutions, MMC uses a serial interface and a single memory stack assembly, making it smaller and simpler than high-pin-count, parallel-interface cards such as CompactFlash, which was previously developed by SanDisk.

It has since evolved into several variants, including the widely used SD card and the eMMC (embedded MMC) which is soldered directly onto a device's circuit board. While removable MMC cards have largely been supplanted by SD cards, eMMC remains common in low-cost smartphones, tablets, and budget laptops due to its compact size and affordability, despite being slower and less upgradeable than modern solid-state drives

History

File:MMC card vs SDHC card undersides angle.jpg
Undersides of an MMC (left) and SD card (right) showing the differences between the two formats

In 1994, SanDisk introduced the CompactFlash format, one of the first commercially successful flash memory card types. CompactFlash outpaced competing formats of the time, including the Miniature Card and SmartMedia. However, the late 1990s saw a proliferation of proprietary memory card formats, such as Memory Stick from Sony and the xD-Picture Card developed by Olympus and Fujifilm, leading to a fragmented and incompatible landscape for removable storage.[1]

In response to this fragmentation, SanDisk partnered with Siemens and Nokia in 1996 to create a universal, compact memory card standard. The resulting format, known as the MultiMediaCard (MMC), was officially introduced in 1997.[1] MMC was designed to be significantly smaller than CompactFlash, with a postage stamp-sized form factor, and to use just seven flat electrical contacts and a simplified serial interface, reducing complexity in host devices. The MultiMediaCard Association (MMCA), was founded in 1998 by 14 companies to promote adoption of the format.[2]

Compared to the physically larger CompactFlash, which relied on 50-pin parallel interfaces and traditional surface-mount assembly, MMC offered a more streamlined and mobile-friendly design, which the MMCA hoped would make it attractive for use in portable consumer electronics such as digital cameras, handheld devices, and mobile phones.

Despite its technical advantages, MMC adoption was limited. Even Nokia, one of the original backers, was slow to integrate MMC into its popular handsets.[1] In an effort to boost adoption, the MMCA introduced revised specifications between 2004 and 2007, including reduced power consumption, support for smaller form factors, and increased storage capacities. However, these updates had limited market impact.

MMC technology served as the foundation for the development of the Secure Digital (SD) card standard. Introduced in 1999 by SanDisk, Panasonic, and Toshiba, SD was based on the MMC electrical interface but added digital rights management (DRM), more durable casing, and a mechanical write-protect switch. These enhancements, along with broad manufacturer support, led SD to surpass MMC in popularity. Many early SD-compatible devices also supported MMC cards.[3]

MMC's most enduring legacy came in the form of its embedded variant, eMMC (embedded MultiMediaCard). First introduced by the JEDEC Solid State Technology Association in 2006 with version 4.0 of the standard, eMMC adapted the MMC architecture for non-removable storage integrated directly onto a device’s motherboard.[4] The eMMC format proved especially successful in smartphones, tablets, Chromebooks, and other low-cost computing devices due to its low cost,[5] compact size, and adequate performance for basic tasks.[6]

On September 23, 2008, the MMCA formally transferred control of the MMC specification to JEDEC.[7] While JEDEC continued to update the eMMC standard, removable MMC cards saw little further development.[6][8] Template:As of, the format has largely faded from use. eMMC itself is gradually being supplanted in performance-oriented applications by newer technologies such as Universal Flash Storage (UFS) and solid-state drives (SSDs), although it remains in use in budget-conscious and embedded devices.

MMC card variants

Template:Multiple image

RS-MMC

Reduced Size MultiMediaCard (RSTemplate:NbhyphMMC), introduced in 2002,[9] is a smaller variant of MMC, measuring approximately Template:Convert, about half the height of a standard MMC.[10] It uses a simple extender to work in standard MMC or SD slots and was available in capacities up to 2 GB. Some manufacturers, including Nokia and Siemens, briefly adopted RSTemplate:NbhyphMMC in their early Symbian-based smartphones and tablets.

DV-MMC

Dual Voltage MMC (DVTemplate:NbhyphMMC, also called the Low Voltage MMC) supported 1.8 V alongside the normal 3.3 V operation to reduce power consumption in mobile devices. This variant was first proposed in 2001,[11] but wasn't widely available until 2004,[12] and was soon overtaken by the more capable MMCplus and MMCmobile formats.

MMCplus, MMCmobile and MMCmicro

File:Mmc-micro.PNG
MMCmicro

The MMCplus and MMCmobile formats were introduced in 2004 and the MMCmicro format in 2005 as part of version 4 of the MMC specification with several enhancements to improve performance and better compete with SD cards.[13][14][15] These enhancements included support for higher clock speeds (26 MHz and 52 MHz alongside the normal 20 MHz) and wider data buses (8Template:Nbhyphbit alongside the previous 1- and 4Template:Nbhyphbit), which combined to enable a 52 Mbit/s transfer rate, alongside dual-voltage support (1.8 V and 3.3 V) carried over from DV‑MMC.[10]

The full‑size enhanced format was marketed as MMCplus, while its smaller counterpart, matching the size of RS-MMC, was known as MMCmobile. Cards have 13 flat electrical contacts to support 8Template:Nbhyphbit data buses.[10] Both formats maintained backward compatibility with devices with standard MMC readers, though without support for some of their advanced features.[16]

The MMCmicro format featured a compact Template:Convert form factor to compete with microSD cards. It supported dual-voltage and high-speed 4‑bit operation, though it lacked the pins required for an 8‑bit bus. MMCmicro cards could be used with an adapter for use in full-size MMC slots.[10]

MiCard

The miCARD (Multiple Interface Card) was a high‑capacity MMC variant proposed in 2007 that could be plugged directly into a USB port eliminating the need for dedicated card slots or separate card readers and could be used in standard MMC/SD slots via an adapter.[17] The card would have been slightly smaller than a RS-MMC/MMCmobile card, but larger than MMCmicro at Template:Convert.[18] Despite backing from several Taiwanese companies, MiCard never reached mass production.

Embedded MMC Script error: No such module "anchor".

File:Samsung Galaxy Tab 2 10.1 - Samsung KLMAG2GE4A-A002-3955.jpg
eMMC chip inside the Samsung Galaxy Tab 2 10.1

The embedded MultiMediaCard (eMMC, officially branded as e•MMC) is a type of internal storage that integrates NAND flash memory,[19] a buffer, and a controller into a single ball grid array (BGA) package. Unlike other forms of removable card-based MMC storage, eMMC is permanently soldered onto a device's printed circuit board (PCB) and is not user-removable or upgradeable. The onboard controller manages tasks such as error correction and data handling, reducing the workload on the device's main processor. eMMC chips use an 8-bit parallel interface and are available in various physical sizes and storage capacities.[20][21]

The eMMC standard was first introduced by the JEDEC Solid State Technology Association in 2006 with version 4.0, which adapted the original card-based MMC specification for embedded (non-removable) and mobile applications.[4] Between 2007 and 2012, the version 4 standard was revised multiple times to improve performance and introduce features such as secure erase and on-system firmware updates. Version 5.0, released in 2013, introduced the HS400 interface mode, enabling theoretical data transfer speeds of up to 400 MB/s, along with enhancements to reliability and boot performance. This was followed by version 5.1 in 2015, which added command queuing and further reliability improvements.[6] The most recent update, version 5.1A, was released in 2019 and included minor refinements to the standard.[8]

eMMC became widely used as the primary storage medium in early smartphones, and later in low-cost laptop computers, Chromebooks, tablet computers, and other compact computing devices. While it was gradually supplanted in higher-performance devices by alternatives such as Universal Flash Storage (UFS) in smartphones and solid-state drives (SSDs) in computers, eMMC continued to be used in entry-level products due to its low cost,[5] compact form factor, low power consumption, and adequate performance for everyday tasks such as web browsing, email, and video streaming.[6]

While eMMC is faster and more power-efficient than traditional hard disk drives, it is slower than most SSDs, especially those using NVMe over PCI Express. These speed limitations make it less suited for applications involving large files or intensive computing needs, such as gaming or video editing. Its lack of upgradeability also limits its appeal in more advanced systems, as users cannot replace or expand storage after purchase.[6]

eMMC versions[22]
Version Introduced Sequential read (MB/s) Sequential write (MB/s) Random read (IOPS) Random write (IOPS)
4.3 2007 52[23] 48[24]
4.5 2012 150 50 7,000 2,000
5.0 2013 250 90 7,000 13,000
5.1 2015 250 125 11,000 13,000


Higher capacity variants of eMMC reach higher writing speeds. While the reading speed of eMMC 5.0 remains constant at 250 MB/s throughout its storage options, a 64 GB eMMC 5.0 writes at up to 90 MB/s, more than six times faster than the 14 MB/s of the lowest storage option of 4 GB.[25]

Similar formats

In 2004, a group of companies—including Seagate and Hitachi—introduced an interface called CE-ATA for small form factor hard disk drives.[26] This interface was electrically and physically compatible with the MMC specification. However, support for further development of the standard ended in 2008.[27]

The game card format used on the PlayStation Vita was found to be based on the MMC standard, but with a different pinout and support for custom initialization commands as well as copy protection.[28]

See also

References

Template:Reflist

External links

Template:Sister project

Template:Memory Cards

Template:Use mdy dates

  1. ↑ a b c Script error: No such module "citation/CS1".
  2. ↑ Script error: No such module "citation/CS1".
  3. ↑ Script error: No such module "citation/CS1".
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  5. ↑ a b Script error: No such module "citation/CS1".
  6. ↑ a b c d e Script error: No such module "citation/CS1".
  7. ↑ Script error: No such module "citation/CS1".
  8. ↑ a b Script error: No such module "citation/CS1".
  9. ↑ Script error: No such module "citation/CS1".
  10. ↑ a b c d Script error: No such module "citation/CS1".
  11. ↑ Script error: No such module "citation/CS1".
  12. ↑ Script error: No such module "citation/CS1".
  13. ↑ Script error: No such module "citation/CS1".
  14. ↑ Script error: No such module "citation/CS1".
  15. ↑ Script error: No such module "citation/CS1".
  16. ↑ Script error: No such module "citation/CS1".
  17. ↑ Script error: No such module "citation/CS1".
  18. ↑ Script error: No such module "citation/CS1".
  19. ↑ Script error: No such module "citation/CS1".
  20. ↑ Script error: No such module "citation/CS1".
  21. ↑ Script error: No such module "citation/CS1".
  22. ↑ Script error: No such module "citation/CS1".
  23. ↑ Script error: No such module "citation/CS1".
  24. ↑ Script error: No such module "citation/CS1".
  25. ↑ Embedded Multimedia Card (eMMC 5.0 HS400) Specification (MLC): 2.1 System Performance
  26. ↑ Script error: No such module "citation/CS1".
  27. ↑ Script error: No such module "citation/CS1".
  28. ↑ Script error: No such module "citation/CS1".
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