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53-571: The group's goals did not include the development of a new consumer flash memory card format. Rather, ONFI seeks to standardize the low-level interface to raw NAND flash chips, which are the most widely used form of non-volatile memory integrated circuits (chips); in 2006, nearly one trillion MiB of flash memory was incorporated into consumer electronics, and production was expected to double by 2007. As of 2006, NAND flash memory chips from most vendors used similar packaging, had similar pinouts , and accepted similar sets of low-level commands. As

106-467: A Samsung 970 EVO NVMe M.2 SSD (2018) with 1 TB of capacity has an endurance rating of 600 TBW. Recovering data from SSDs presents challenges due to the non-linear and complex nature of data storage in solid-state drives. The internal operations of SSDs vary by manufacturer, with commands (e.g. TRIM and the ATA Secure Erase) and programs like (e.g. hdparm ) being able to erase and modify

159-428: A cache (configurable as write-through or write-back ) for a conventional, magnetic hard disk drive. A similar technology is available on HighPoint 's RocketHybrid PCIe card. Solid-state hybrid drives (SSHDs) are based on the same principle, but integrate some amount of flash memory on board of a conventional drive instead of using a separate SSD. The flash layer in these drives can be accessed independently from

212-474: A commodity product, like SDRAM or hard disk drives. It is incorporated into many personal computer and consumer electronics products such as USB flash drives , MP3 players , and solid-state drives . Product designers wanted newer NAND flash chips, for example, to be as easily interchangeable as hard disks from different manufacturers. The effort to standardize NAND flash may be compared to earlier standardization of electronic components . For example,

265-409: A live SD operating system are easily write-locked . Combined with a cloud computing environment or other writable medium, an OS booted from a write-locked SD card is reliable, persistent and impervious to permanent corruption. In 2011, Intel introduced a caching mechanism for their Z68 chipset (and mobile derivatives) called Smart Response Technology , which allows a SATA SSD to be used as

318-720: A niche , while in mobile phones and PDAs, the memory card has become smaller. Initially memory cards were expensive, costing US$ 3 per megabyte of capacity in 2001; this led to the development of miniaturized rotating disk memory devices such as the Microdrive , PocketZip and Dataplay . The Microdrive had higher capacities than memory cards at the time. All three concepts became obsolete once flash memory prices became lower and their capacities became higher by 2006. New products of Sony (previously only using Memory Stick) and Olympus (previously only using XD-Card) have been offered with an additional SD-Card slot beginning in 2010. Effectively

371-411: A constant power supply to retain data. DRAM-based SSDs are typically used in specialized applications where performance is prioritized over cost or non-volatility. Many SSDs, such as NVDIMM devices, are equipped with backup power sources such as internal batteries or external AC/DC adapters. These power sources ensure data is transferred to a backup system (usually NAND flash or another storage medium) in

424-471: A constant power supply. NAND flash-based SSDs store data in semiconductor cells, with the specific architecture influencing performance, endurance, and cost. There are various types of NAND flash memory, categorized by the number of bits stored in each cell: Over time, SSD controllers have improved the efficiency of NAND flash, incorporating techniques such as interleaved memory , advanced error correction, and wear leveling to optimize performance and extend

477-803: A controller, which manages the data flow between the NAND memory and the host computer. The controller is an embedded processor that runs firmware to optimize performance, managing data, and ensuring data integrity. Some of the primary functions performed by the controller are: The overall performance of an SSD can scale with the number of parallel NAND chips and the efficiency of the controller. For example, controllers that enable parallel processing of NAND flash chips can improve bandwidth and reduce latency. Micron and Intel pioneered faster SSDs by implementing techniques such as data striping and interleaving to enhance read/write speeds. More recently, SandForce introduced controllers that incorporate data compression to reduce

530-449: A device. In 2001, SmartMedia alone captured 50% of the digital camera market and CF had captured the professional digital camera market. However, by 2005, SD and similar MMC cards had nearly taken over SmartMedia's spot, though not to the same level and with stiff competition coming from Memory Stick variants, as well as CompactFlash. In industrial and embedded fields, even the venerable PC card (PCMCIA) memory cards still manage to maintain

583-743: A limited lifetime number of writes, and also slow down as they reach their full storage capacity. SSDs also have internal parallelism that allows them to manage multiple operations simultaneously, which enhances their performance. Unlike HDDs and similar electromechanical magnetic storage , SSDs do not have moving mechanical parts, which provides advantages such as resistance to physical shock, quieter operation, and faster access times. Their lower latency results in higher input/output rates (IOPS) than HDDs. Some SSDs are combined with traditional hard drives in hybrid configurations, such as Intel's Hystor and Apple's Fusion Drive . These drives use both flash memory and spinning magnetic disks in order to improve

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636-647: A lithium battery to keep the contents in the SRAM. These cards were faster than their flash counterparts. Some of the first PCMCIA cards had capacities of 1 to 5 MB and cost US$ 100 per MB. Other early cards such as the Bee Card contained non-modifiable ROM , Write once read many EPROM or rewriteable EEPROM memory. In 1992, SanDisk introduced FlashDisk, a PCMCIA card and one of the first memory cards that did not require battery power to retain its contents, as it used flash memory. In 1994, memory card formats smaller than

689-578: A lower cost alternative to ROM cartridges . Several competing and incompatible memory card formats were developed by several vendors, such as for example the Bee Card , Astron SoftCards, Sega Cards, NEC UltraLite memory cards, and the Mitsubishi Melcard which came in variants using 60 and 50 connector pins. The Sega Card was developed as a cheaper alternative to game cartridges. Some memory cards were used for memory expansion in laptops. JEIDA,

742-864: A lower cost than pure SSDs. An SSD stores data in semiconductor cells, with its properties varying according to the number of bits stored in each cell (between 1 and 4). Single-level cells (SLC) store one bit of data per cell and provide higher performance and endurance. In contrast, multi-level cells (MLC), triple-level cells (TLC), and quad-level cells (QLC) store more data per cell but have lower performance and endurance. SSDs using 3D XPoint technology, such as Intel’s Optane, store data by changing electrical resistance instead of storing electrical charges in cells, which can provide faster speeds and longer data persistence compared to conventional flash memory. SSDs based on NAND flash slowly leak charge when not powered, while heavily-used consumer drives may start losing data typically after one to two year in storage. SSDs have

795-445: A result, when more capable and inexpensive models of NAND flash become available, product designers can incorporate them without major design changes. However, "similar" operation is not optimal: subtle differences in timing and command set mean that products must be thoroughly debugged and tested when a new model of flash chip is used in them. When a flash controller is expected to operate with various NAND flash chips, it must store

848-933: A small amount of volatile DRAM as a cache, similar to the buffers in hard disk drives. This cache can temporarily hold data while it is being written to the flash memory, and it also stores metadata such as the mapping of logical blocks to physical locations on the SSD. Some SSD controllers, like those from SandForce, achieve high performance without using an external DRAM cache. These designs rely on other mechanisms, such as on-chip SRAM, to manage data and minimize power consumption. Additionally, some SSDs use an SLC cache mechanism to temporarily store data in single-level cell (SLC) mode, even on multi-level cell (MLC) or triple-level cell (TLC) SSDs. This improves write performance by allowing data to be written to faster SLC storage before being moved to slower, higher-capacity MLC or TLC storage. On NVMe SSDs, Host Memory Buffer (HMB) technology allows

901-578: A sudden power loss. Some consumer SSDs have built-in capacitors to save critical data such as the Flash Translation Layer (FTL) mapping table. Examples include the Crucial M500 and Intel 320 series. Enterprise-class SSDs, such as the Intel DC S3700 series, often come with more robust power-loss protection mechanisms like supercapacitors or batteries. The host interface of an SSD refers to

954-735: A system in the same way as HDDs, SSDs are used in a variety of devices, including personal computers , enterprise servers , and mobile devices . However, SSDs are generally more expensive on a per-gigabyte basis and have a finite number of write cycles, which can lead to data loss over time. Despite these limitations, SSDs are increasingly replacing HDDs, especially in performance-critical applications and as primary storage in many consumer devices. SSDs come in various form factors and interface types, including SATA , PCIe , and NVMe , each offering different levels of performance. Hybrid storage solutions, such as solid-state hybrid drives (SSHDs), combine SSD and HDD technologies to offer improved performance at

1007-615: A table of them in its firmware so that it knows how to deal with differences in their interfaces. This increases the complexity and time-to-market of flash-based devices, and means they are likely to be incompatible with future models of NAND flash, unless and until their firmware is updated. Thus, one of the main motivations for standardization of NAND flash was to make it easier to switch between NAND chips from different producers, thereby permitting faster development of NAND-based products and lower prices via increased competition among manufacturers. By 2006, NAND flash became increasingly

1060-906: Is a type of solid-state storage device that uses integrated circuits to store data persistently . It is sometimes called semiconductor storage device , solid-state device , or solid-state disk . SSDs rely on non-volatile memory, typically NAND flash , to store data in memory cells. The performance and endurance of SSDs vary depending on the number of bits stored per cell, ranging from high-performing single-level cells (SLC) to more affordable but slower quad-level cells (QLC). In addition to flash-based SSDs, other technologies such as 3D XPoint offer faster speeds and higher endurance through different data storage mechanisms. Unlike traditional hard disk drives (HDDs), SSDs have no moving parts, allowing them to deliver faster data access speeds, reduced latency, increased resistance to physical shock, lower power consumption, and silent operation. Often interfaced to

1113-648: Is added. ONFI 4.1 also includes errata to the ONFI 4.0 specification. Version 4.2 , published on February 12, 2020, extends NV-DDR3 I/O speeds to 1333MT/s, 1466MT/s and 1600MT/s. The BGA-252b four channel package is introduced which has a smaller footprint than the existing BGA-272b four channel package. To enable higher IOPS multi-plane operations, addressing restrictions related to multi-plane operations are relaxed. Version 5.0 , Published in May 2021, ONFI5.0 extends NV-DDR3 I/O speeds up to 2400MT/s. A new NV-LPDDR4 lower power interface

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1166-573: Is an electronic data storage device used for storing digital information, typically using flash memory . These are commonly used in digital portable electronic devices , such as digital cameras as well as in many early games consoles such as the Nintendo Wii . They allow adding memory to such devices using a card in a socket instead of protruding USB flash drives . Common types of flash memory card include SD cards (including microSD), Sony's Memory Stick and CompactFlash . As of 2024 , SD cards are

1219-496: Is infrequently changed (cold data) from heavily used blocks, so that data that changes more frequently (hot data) can be written to those blocks. This helps distribute wear more evenly across the entire SSD. However, this process introduces additional writes, known as write amplification, which must be managed to balance performance and durability. Most SSDs use non-volatile NAND flash memory for data storage, primarily due to its cost-effectiveness and ability to retain data without

1272-563: Is introduced with speeds up to 2400MT/s. With the NV-LPDDR4 interface, an optional Data Bus Inversion (DBI) feature is defined. New smaller footprint BGA-178b, BGA-154b and BGA-146b packages are added. ONFI5.0 also includes other errata related to the ONFI4.2 specification. ONFI created the Block Abstracted NAND addendum specification to simplify host controller design by relieving the host of

1325-405: The 7400 series of TTL digital integrated circuits were originally produced by Texas Instruments , but had become a de facto standard family by the late 1970s. These ICs are manufactured as commodity parts by a number of different vendors. This has allowed designers to freely mix 7400 components from different vendors—and even to mix components based on different logic families , once

1378-572: The JEDEC was published in October 2012. Version 3.1 , published in october of 2012, includes errata to the original ONFI 3.0 specification, adds LUN SET/GET Features commands, and implements additional data setup and hold values for NV-DDR2 interface. Version 3.2 , published on July 23, 2013, raised the data rate to 533 MB/s. Version 4.0 , published on April 17, 2014, introduced the NV-DDR3 interface increases

1431-644: The Japan Electronic Industry Development Association , began to work on a standard for memory cards in 1985, and developed the JEIDA memory card in 1986. The Personal Computer Memory Card International Association (PCMCIA) was an industry association created in 1989 to promote a standard for memory cards in PCs, and worked closely with JEIDA, adopting their 68 pin connector design. The specification for PCMCIA type I cards, later renamed PC Cards ,

1484-475: The format war has turned in SD-Card's favor. (full-duplex) Many older video game consoles used memory cards to hold saved game data. Cartridge -based systems primarily used battery-backed volatile RAM within each individual cartridge to hold saves for that game. Cartridges without this RAM may have used a password system , or would not save progress at all. The Neo Geo AES , released in 1990 by SNK ,

1537-466: The magnetic storage by the host using ATA-8 commands, allowing the operating system to manage it. For example, Microsoft's ReadyDrive technology explicitly stores portions of the hibernation file in the cache of these drives when the system hibernates, making the subsequent resume faster. Dual-drive hybrid systems are combining the usage of separate SSD and HDD devices installed in the same computer, with overall performance optimization managed by

1590-696: The sixth generation of video game consoles , memory cards were based on proprietary formats ; Later systems used established industry formats for memory cards, such as FAT32 . Home consoles commonly use hard disk drive storage for saved games and allow the use of USB flash drives or other card formats via a memory card reader to transport game saves and other game information. Though some consoles have implemented cloud storage saving, most portable gaming systems still rely on custom memory cartridges to store program data, due to their low power consumption, smaller physical size and reduced mechanical complexity. Solid-state drive A solid-state drive ( SSD )

1643-552: The 74HCT sub-family become available (consisting of CMOS components with TTL-compatible logic levels). The ONFI consortium included manufacturers of NAND flash memory such as Hynix , Intel , Micron Technology , Phison , Western Digital , Sony and Spansion . Samsung , the world's largest manufacturer of NAND flash, was absent in 2006. Vendors of NAND flash-based consumer electronics and computing products are also members. ONFI produced specifications for standard interface to NAND flash chips. Version 1.0 of this specification

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1696-560: The PC Card arrived. The first one was CompactFlash and later SmartMedia and Miniature Card . The desire for smaller cards for cell-phones, PDAs , and compact digital cameras drove a trend that left the previous generation of "compact" cards looking big. In 2000 the SD card was announced. SD was envisioned as a single memory card format for several kinds of electronic devices, that could also function as an expansion slot for adding new capabilities for

1749-504: The SSD to use a portion of the system’s DRAM instead of relying on a built-in DRAM cache, reducing costs while maintaining a high level of performance. In certain high-end consumer and enterprise SSDs, larger amounts of DRAM are included to cache both file table mappings and written data, reducing write amplification and enhances overall performance. Higher-performing SSDs may include a capacitor or battery, which helps preserve data integrity in

1802-446: The amount of data written to the flash memory, potentially increasing both performance and endurance. Wear leveling is a technique used in SSDs to ensure that write and erase operations are distributed evenly across all blocks of the flash memory. Without this, specific blocks could wear out prematurely due to repeated use, reducing the overall lifespan of the SSD. The process moves data that

1855-418: The bits of a deleted file. The JEDEC Solid State Technology Association (JEDEC) has established standards for SSD reliability metrics, which include: In a distributed computing environment, SSDs can be used as a distributed cache layer that temporarily absorbs the large volume of user requests to slower HDD-based backend storage systems. This layer provides much higher bandwidth and lower latency than

1908-426: The complete loss of the drive. Most of the advantages of solid-state drives over traditional hard drives are due to their ability to access data completely electronically instead of electromechanically, resulting in superior transfer speeds and mechanical ruggedness. On the other hand, hard disk drives offer significantly higher capacity for their price. In traditional HDDs, a rewritten file will generally occupy

1961-669: The complexities of ECC, bad block management, and other low-level NAND management tasks. The ONFI Block Abstracted NAND revision 1.1 specification adds the high speed source synchronous interface, which provides up to a 5X improvement in bandwidth compared with the traditional asynchronous NAND interface. The NAND Connector Specification was ratified in April 2008. It specifies a standardized connection for NAND modules (similar to DRAM DIMMs) for use in applications like caching and solid-state drives (SSDs) in PC platforms. Memory card A memory card

2014-691: The computer like hard drives. In contrast, memory cards (such as Secure Digital (SD), CompactFlash (CF), and many others) were originally designed for digital cameras and later found their way into cell phones, gaming devices, GPS units, etc. Most memory cards are physically smaller than SSDs, and designed to be inserted and removed repeatedly. SSDs have different failure modes from traditional magnetic hard drives. Because solid-state drives contain no moving parts, they are generally not subject to mechanical failures. However, other types of failures can occur. For example, incomplete or failed writes due to sudden power loss may be more problematic than with HDDs, and

2067-593: The computer user, or by the computer's operating system software. Examples of this type of system are bcache and dm-cache on Linux , and Apple's Fusion Drive . The primary components of an SSD are the controller and the memory used to store data. Traditionally, early SSDs used volatile DRAM for storage, but since 2009, most SSDs utilize non-volatile NAND flash memory, which retains data even when powered off. Flash memory SSDs store data in metal–oxide–semiconductor (MOS) integrated circuit chips, using non-volatile floating-gate memory cells. Every SSD includes

2120-509: The electrical resistance of materials in its cells, offering much faster access times than NAND flash. 3D XPoint-based SSDs, such as Intel’s Optane drives, provide lower latency and higher endurance than NAND-based drives, although they are more expensive per gigabyte. Drives known as hybrid drives or solid-state hybrid drives (SSHDs) use a hybrid of spinning disks and flash memory. Some SSDs use magnetoresistive random-access memory (MRAM) for storing data. Many flash-based SSDs include

2173-535: The event of an unexpected power loss. The capacitor or battery provides enough power to allow the data in the cache to be written to the non-volatile memory, ensuring no data is lost. In some SSDs that use multi-level cell (MLC) flash memory, a potential issue known as "lower page corruption" can occur if power is lost while programming an upper page. This can result in previously written data becoming corrupted. To address this, some high-end SSDs incorporate supercapacitors to ensure all data can be safely written during

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2226-493: The event of power loss, preventing data corruption or loss. Similarly, ULLtraDIMM devices use components designed for DIMM modules, but only use flash memory, similar to a DRAM SSD. DRAM-based SSDs are often used for tasks where data must be accessed at high speeds with low latency, such as in high-performance computing or certain server environments. 3D XPoint is a type of non-volatile memory technology developed by Intel and Micron, announced in 2015. It operates by changing

2279-467: The failure of a single chip may result in the loss of all data stored on it. Nonetheless, studies indicate that SSDs are generally reliable, often exceed their manufacturer-stated lifespan and having lower failure rates than HDDs. However, studies also note that SSDs experience higher rates of uncorrectable errors, which can lead to data loss, compared to HDDs. The endurance of an SSD is typically listed on its datasheet in one of two forms: For example,

2332-485: The lifespan of the drive. Lower-end SSDs often use QLC or TLC memory, while higher-end drives for enterprise or performance-critical applications may use MLC or SLC. In addition to the flat (planar) NAND structure, many SSDs now use 3D NAND (or V-NAND), where memory cells are stacked vertically, increasing storage density while improving performance and reducing costs. Some SSDs use volatile DRAM instead of NAND flash, offering very high-speed data access but requiring

2385-631: The maximum switching speed from 533 MB/s to 800 MB/s, providing a performance boost of up to 50% for high performance applications enabled by solid-state NAND storage components. Version 4.1 , published on December 12, 2017, extends NV-DDR3 I/O speeds to 1066 MT/s and 1200MT/s.  For better signaling performance, ONFI 4.1 adds Duty Cycle Correction (DCC), Read and Write Training for speeds greater than 800MT/s, support for lower pin cap devices with 37.5 Ohms default output resistance, and devices which require data burst exit and restart for long data input and output pauses.  For lower power, 2.5V Vcc support

2438-420: The most common type of memory cards. The basis for memory card technology is flash memory . It was invented by Fujio Masuoka at Toshiba in 1980 and commercialized by Toshiba in 1987. The development of memory cards was driven in the 1980s by the need for an alternative to floppy disk drives that had lower power consumption, had less weight and occupied less volume in laptops. Some were also marketed as

2491-741: The performance characteristics such as rotational latency and seek time . As SSDs do not need to spin or seek to locate data, they are vastly superior to HDDs in such tests. However, SSDs have challenges with mixed reads and writes, and their performance may degrade over time. Therefore, SSD testing typically looks at when the full drive is first used, as the new and empty drive may have much better write performance than it would show after only weeks of use. The reliability of both HDDs and SSDs varies greatly among models. Some field failure rates indicate that SSDs are significantly more reliable than HDDs. However, SSDs are sensitive to sudden power interruption, sometimes resulting in aborted writes or even cases of

2544-554: The performance of frequently-accessed data. Traditional interfaces (e.g. SATA and SAS ) and standard HDD form factors allow such SSDs to be used as drop-in replacements for HDDs in computers and other devices. Newer form factors such as mSATA , M.2 , U.2 , NF1 / M.3 / NGSFF , XFM Express ( Crossover Flash Memory , form factor XT2) and EDSFF and higher speed interfaces such as NVM Express (NVMe) over PCI Express (PCIe) can further increase performance over HDD performance. Traditional HDD benchmarks tend to focus on

2597-543: The same location on the disk surface as the original file, whereas in SSDs the new copy will often be written to different NAND cells for the purpose of wear leveling . The wear-leveling algorithms are complex and difficult to test exhaustively. As a result, one major cause of data loss in SSDs is firmware bugs. While both memory cards and most SSDs use flash memory, they have very different characteristics, including power consumption, performance, size, and reliability. Originally, solid state drives were shaped and mounted in

2650-638: The storage system would, and can be managed in a number of forms, such as a distributed key-value database and a distributed file system . On supercomputers, this layer is typically referred to as burst buffer . Flash-based solid-state drives can be used to create network appliances from general-purpose personal computer hardware. A write protected flash drive containing the operating system and application software can substitute for larger, less reliable disk drives or CD-ROMs. Appliances built this way can provide an inexpensive alternative to expensive router and firewall hardware. SSDs based on an SD card with

2703-460: Was first released in 1990, and unified the JEIDA memory card standard with the PC Card standard. This format later included support for other devices besides memory cards. PC Card was among the first commercial memory card formats to come out, but is mainly used in industrial applications and to connect I/O devices such as modems . Some early memory cards used SRAM as a storage medium, which required

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2756-613: Was released on December 28, 2006, and made available at no cost from the ONFI web site. Samsung was still not a participant. It specified: A verification product was announced in June 2009. Version 2.3 was published in August 2010. It included a protocol called EZ-NAND that hid ECC details. Version 3.0 was published in March 2011. It required fewer chip-enable pins enabling more efficient printed circuit board routing. A standard developed jointly with

2809-466: Was the first video game console able to use a memory card. AES memory cards were also compatible with Neo Geo MVS arcade cabinets , allowing players to migrate saves between home and arcade systems and vice versa. Memory cards became commonplace when home consoles moved to read-only optical discs for storing the game program, beginning with systems such as the TurboGrafx-CD and Sega-CD . Until

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