flash memory

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flash memory

[¦flash ′mem·rē]
(computer science)
A type of electrically erasable programmable read-only memory (EEPROM). While EPROM is reprogrammed bit-by-bit, flash memory is reprogrammed in blocks, making it faster. It is nonvolatile.

flash memory

flash memory

(1) For Adobe's multimedia authoring and playback system, see Flash.

(2) Flash memory is the most popular non-volatile, rewritable storage chip. Comprised of cells that hold a charge without power, flash memory is extremely durable and used in just about every electronic device, including cameras, smartphones, tablets, music players and USB drives. It is also the storage component in solid state drives (SSDs), which increasingly replace hard drives in computers and servers. All flash memory eventually wears out, but most users will have many years of service (see SSD write cycle). See solid state drive.

Evolving from the EEPROM chip, flash was invented by Toshiba in the mid-1980s and named after its ability to erase a block of data "in a flash." However, this block erasing is its least desirable feature because it adds a step. To change what is stored in flash memory, the cells must first be erased in blocks ranging from 16KB to 512KB in length. Then the cells can be written.

NOR Flash for Execution
NOR flash is used for program execution similar to RAM. Introduced by Intel in 1988, NOR supports one-byte random access, which means a program's instructions are executed directly from the NOR flash the same way computers execute instructions in RAM. Unlike RAM, NOR flash does not require power to hold its content. See computer and RAM.

NAND Flash for Storage
Toshiba developed the less costly NAND flash in 1989. It has denser cells and faster erasing and writing than NOR. For example, in a digital camera, an internal NOR chip holds the software, but the removable memory cards are composed of NAND chips. In a computer, a translation layer makes a NAND flash solid state drive (SSD) function like a hard drive for both program and data storage (see FTL). Just like a hard drive, instructions in a program are first read into RAM and then executed. For more on flash architecture, see EEPROM, NAND flash and MLC. See charge trap flash, USB drive, memory card, solid state drive, flash BIOS, early memories and future memory chips.


From Spinning Platters to Flash
Slowly but surely, flash-based solid state drives (SSDs) are replacing the computer's hard drives for storage. Not only are SSDs faster, there is no read/write head to accidentally scratch a platter's surface (see head crash). See solid state drive.







USB Drives "Are" Flash Memory
The ubiquitous USB drives are not much more than a NAND flash memory chip.







Memory Cards Are the Camera's "Film"
NAND flash memory cards such as this 16GB SD Card are used in all modern cameras and camcorders. SD Cards are very popular, and they can hold up to 512GB. See SD Card and memory card.







Disk Pack Storage - 1970s
The SD Card example in the digital camera above holds eight times more storage than all the disk drives in this room full of ICL computers. See disk pack. (Images courtesy of The National Museum of Computing, Milton Keynes, U.K., www.tnmoc.org)







Flash For Sale
This 2014 Micro Center ad highlighted the flash memory products people use every day. Class 10 SD Cards means a minimum of 10 MBytes/sec write speed for HD video recording. See SD Card classes. (Image courtesy of Micro Center, www.microcenter.com)
References in periodicals archive ?
Macronix is a leader in Non-Volatile Memory and ranked #2 in the NOR Flash market by independent sources, a fact that is being increasingly recognized by ecosystem leaders.
Designers of high-performance systems require fast, low-pin-count Quad SPI NOR Flash memories, and our newest FL-L device is tailor-made to deliver the bandwidth and small form factor for these applications, said Anup Sidhu, Director of SPI Product Marketing at Cypress.
1 supplier of non-volatile memory chips including NOR Flash chips and has numbered Nintendo among its major customers.
Customers wishing to benefit from the cost advantages of transitioning to 90nm MirrorBit Flash memory devices can do so easily with Spansion's built-in support for the flexible migration of existing handset hardware and software associated with the migration from 110nm to 90nm MirrorBit NOR Flash memory.
Tags / Keywords: SST39VF401C , SST39VF402C , 39VF401C , 39VF402C , SST39LF401C , SST39LF402C , 39LF401C , 39LF402C , 4 Mb parallel Flash , NOR Flash , MPF+ , Multi-Purpose Flash Plus
Availability Cypress's 256Mb FL-L Quad SPI NOR Flash memory is now sampling in space-saving 24-ball BGA, 16-pin SOIC and 8-contact WSON packages.
Currently, the company's contract products include LCD drive ICs, CMOS sensors, NOR Flash chips, NAND Flash memory chips, and consumer DRAM.
Chip maker Intel Corp has unveiled several new NOR flash memory products aimed at the mobile phone and embedded market.
As the world's leading NOR Flash memory brand, Spansion memory is a central component in many wireless designs," said Alistair Greenhill, Director of Marketing, Development Systems, ARM.
With a mushrooming need for Flash memory to support the myriad of innovative wearables coming to market, Macronix has accelerated development of related product solutions, such as the new MX25R wide-voltage/ultra-low power NOR Flash family, to reinforce its position as a leading memory provider.
has secured rush orders for NOR Flash memory chips after the recent devastating earthquake in Japan, according to corporate president Minn Wu.
The new NOR Flash products are targeted for use in networking, computing, consumer, and mobile applications.