Flash memory is a type of non volatile memory that can be electronically
Flash memory is a type of non volatile memory that can be electronically
FLASH MEMORY
Flash memory is a non-volatile computer storage that can be electrically erased and reprogrammed. It is a technology that is primarily used in memory cards and USB flash drives for general storage and transfer of data between computers and other digital products. It is a specific type of EEPROM (Electrically Erasable Programmable Read-Only Memory) that is erased and programmed in large blocks. In early flash memory the entire chip had to be erased at once.
Flash memory costs far less than byte-programmable EEPROM and therefore has become the dominant technology. Example applications include PDAs (personal digital assistants), laptop computers, digital audio players, digital cameras and mobile phones.
Since flash memory is non-volatile, no power is needed to maintain the information stored in the chip. In addition, flash memory offers fast read access (although not as fast as volatile DRAM memory used for main memory in PCs) and better kinetic shock resistance than hard disks. These characteristics explain the popularity of flash memory in portable devices. Another feature of flash memory is that when packaged in a «memory card,» it is enormously durable, being able to withstand intense pressure, extremes of temperature, and even immersion in water.
Flash memory (both NOR and NAND types) was invented by Dr. F. Masuoka while working for Toshiba in 1980. He presented his invention at the International Electron Devices Meeting held in San Francisco, California in 1984. Intel Corporation saw the massive potential of the invention and introduced the first commercial NOR type flash chip in 1988. NOR-based flash was the basis of early flash-based removable media; CompactFlash was originally based on it, though later cards moved to less expensive NAND flash which was announced by Toshiba at the International Electron Devices Meeting in 1987. NAND flash is similar to other secondary storage devices such as hard disks and optical media, and is thus very suitable for use in mass-storage devices such as memory cards. The first NAND-based removable media format was SmartMedia, and many others have followed, including MultiMediaCard, Secure Digital, Memory Stick and xD-Picture Card. A new generation of memory card formats, including RS-MMC, miniSD and microSD, and Intelligent Stick, feature extremely small form factors. For example, the microSD card has an area of just over 1.5 cm², with a thickness of less than 1 mm; microSD capacities range from 64 MB to 16 GB, as of August 2009.
1. Give Russian equivalents of the following words and word combinations. Transcribe them.
Flash memory is a type of non-volat
Flash memory is used in several ways:
· Many PCs have their BIOS (basic input/output system) stored on a flash memory chip so it can be updated if necessary.
· Modems use flash memory because it allows the manufacturer to support new protocols.
· USB flash drives are used to save and move MP3s and other data files between computers.
They are more easily transported than external hard drives because they use solid-state technology, meaning that they don’t have fragile moving parts that can break if dropped. However, USB flash drives have less storage capacity than hard drives.
New U3 smart drives allow users to store both applications and data. They have two drive partitions and can carry applications that run on the host computer without requiring installation.
Flash memory cards are used to store images on cameras, to back up data on PDAs, to transfer games in video consoles, to record voice and music on MP3 players or to store movies on MP4 players. They are as small as a stamp, and capacity can range from 8MB to several gigabytes. The only limitation is that flash cards are often not interchangeable between devices. Some formats include: CompactFlash, Secure Digital, MultiMedia Card, miniSD card, and xD-Picture Card. Sony has its own product called the Memory Stick, used in its digital still cameras, video camcorders and the PlayStation Portable. The photos stored in a digital camera can be offioaded to a computer via cable or wirelessly. Another option is to have a flash card reader permanently connected to your PC; you simply eject the card from the camera and put it into the reader instead of having to plug the camera in.
The future of hard drives may be hybrid hard drives. Hybrid hard drives 70 combine a magnetic hard disk and flash memory into one device. This allows computers to boot, or 75 start, more quickly, and also reduces power consumption.
Flash memory is a type of non-volat
Flash memory is used in several ways:
· Many PCs have their BIOS (basic input/output system) stored on a flash memory chip so it can be updated if necessary.
· Modems use flash memory because it allows the manufacturer to support new protocols.
· USB flash drives are used to save and move MP3s and other data files between computers.
They are more easily transported than external hard drives because they use solid-state technology, meaning that they don’t have fragile moving parts that can break if dropped. However, USB flash drives have less storage capacity than hard drives.
New U3 smart drives allow users to store both applications and data. They have two drive partitions and can carry applications that run on the host computer without requiring installation.
Flash memory cards are used to store images on cameras, to back up data on PDAs, to transfer games in video consoles, to record voice and music on MP3 players or to store movies on MP4 players. They are as small as a stamp, and capacity can range from 8MB to several gigabytes. The only limitation is that flash cards are often not interchangeable between devices. Some formats include: CompactFlash, Secure Digital, MultiMedia Card, miniSD card, and xD-Picture Card. Sony has its own product called the Memory Stick, used in its digital still cameras, video camcorders and the PlayStation Portable. The photos stored in a digital camera can be offioaded to a computer via cable or wirelessly. Another option is to have a flash card reader permanently connected to your PC; you simply eject the card from the camera and put it into the reader instead of having to plug the camera in.
The future of hard drives may be hybrid hard drives. Hybrid hard drives 70 combine a magnetic hard disk and flash memory into one device. This allows computers to boot, or 75 start, more quickly, and also reduces power consumption.
Flash memory is a type of non-volat
Unlike RAM, which is volatile, flash memory retains the information stored in the chip when the power is turned off. This makes it ideal for use in digital cameras, laptops, network switches, video game cards, mobile phones and portable multimedia players. In addition, it offers fast read access times (although not as fast as RAM), with transfer rates of 12MB per second. Unlike ROM chips, flash memory chips are rewritable, so you can update programs via software.
Inside the chip, data is stored in several floating gate transistors, called cells. Each cell traditionally stores one bit of data (1 = erased and 0 = programmed). New devices have a multi-level cell structure so 20 they can store more that one bit per cell. The chips are constructed with either NOR or NAND gates. NOR chips function like a computer’s main memory, while NAND works like a hard drive. For example, in a camera, NOR flash contains the camera’s internal software, while NAND flash is used to store the images.
Flash memory is used in several ways:
· Many PCs have their BIOS (basic input/output system) stored on a flash memory chip so it can be updated if necessary.
· Modems use flash memory because it allows the manufacturer to support new protocols.
· USB flash drives are used to save and move MP3s and other data files between computers.
They are more easily transported than external hard drives because they use solid-state technology, meaning that they don’t have fragile moving parts that can break if dropped. However, USB flash drives have less storage capacity than hard drives.
New U3 smart drives allow users to store both applications and data. They have two drive partitions and can carry applications that run on the host computer without requiring installation.
Flash memory cards are used to store images on cameras, to back up data on PDAs, to transfer games in video consoles, to record voice and music on MP3 players or to store movies on MP4 players. They are as small as a stamp, and capacity can range from 8MB to several gigabytes. The only limitation is that flash cards are often not interchangeable between devices. Some formats include: CompactFlash, Secure Digital, MultiMedia Card, miniSD card, and xD-Picture Card. Sony has its own product called the Memory Stick, used in its digital still cameras, video camcorders and the PlayStation Portable. The photos stored in a digital camera can be offioaded to a computer via cable or wirelessly. Another option is to have a flash card reader permanently connected to your PC; you simply eject the card from the camera and put it into the reader instead of having to plug the camera in.
The future of hard drives may be hybrid hard drives. Hybrid hard drives 70 combine a magnetic hard disk and flash memory into one device. This allows computers to boot, or 75 start, more quickly, and also reduces power consumption.
What is Flash Memory? – Definition
By Dinesh Thakur
Definition : Flash memory (Known as Flash Storage) is a type of non-volatile storage memory that can be written or programmed in units called “Sector” or a “Block.” Flash Memory is EEPROM (Electronically Erasable Programmable Read-Only Memory) means that it can retain its contents when the power supply removed, but whose contents can be quickly erased and rewritten at the byte level by applying a short pulse of higher voltage. This is called flash erasure, hence the name. Flash memory is currently both too expensive and too slow to serve as main memory.
Flash memory (sometimes called “Flash RAM”) is a distinct EEPROM that can read block-wise. Typically the sizes of the block can be from hundreds to thousands of bits. Flash Storage block can be divided into at least two logical sub-blocks.
Flash memory mostly used in consumer storage devices, and for networking technology. It commonly found in mobile phones, USB flash drives, tablet computers, and embedded controllers.
Flash memory is often used to hold control code such as the basic input/output system (BIOS) in a personal computer. When BIOS needs to be changed (rewritten), the flash memory can be written to in block (rather than byte) sizes, making it easy to update. On the other hand, flash memory is not used as random access memory (RAM) because RAM needs to be addressable at the byte (not the block) level.
Flash memories are based on Floating-Gate Transistors. Floating gate transistors are used in memory to store a bit of information. Flash memories are used in the device to store a large number of songs, images, files, software, and video for an extended period,etc.
We’ll be covering the following topics in this tutorial:
History Flash Memory
In 1980’s Flash memory as invented by Fujio Masuoka, while working in Toshiba. In 1988, Intel introduced NOR flash memory chip having random access to memory location. These NOR chips were a well-suited replacement for older ROM chips. In 1989, with more improvement, NAND flash memory was introduced by Toshiba. NAND flash memory is similar to a Hard disk with more data storage capacity. After that, there has been a rapid growth in flash memory over the years passes.
Types of Flash Memory
Flash memory is available in two kinds NAND Flash and NOR Flash Memory. NAND and NOR flash memory both have different architecture and used for specific purpose.
NAND Flash Memory
In today is an environment where all devices require high data density, faster speed access and cost-effective chip for data storage. NAND memory has needed less chip area hence more data density. NAND Memory used the concept of the block to access and erases the data. Each block contains the different size of pages various from bytes. MMU (Memory Management Unit) helps NAND to the first page the content or copied into RAM and then executed.
NOR Flash Memory
In the circuit of flash memory, memory cells are connected in parallel. It provides random or sequentially access memory. Data Reading process for NOR and RAM are similar. We can execute the code directly from NOR without copying into RAM. NOR memory ideal for runs small code instructions program. It referred to Code-storage applications. It used for low-density applications.
NOR flash provides support to bad block management. Bad block in memory is handled by controller devices to improve functionality.
We can use the combination of both NOR and NAND memory. NOR (software ROM) used for instruction execution,and NAND used for non-volatile data storage.
Limitation of Flash Memory
Although Flash memory gives many advantages, yet it has some flaw.
1) We can quickly read or programmed a byte at a time, but we cannot erase a byte or word. It can delete data in blocks at a time.
2) Bit flipping: Bit Flipping problem is more occur in NAND memory as compare to NOR. In Bit Flipping, a bit get reversed and create errors. For checking and correcting the bit error (EDC/ECC) detection and error correction code are implemented.
3) Bad block: Bad block are the blocks which can’t be used for storage. If scanning system gets fails to check and recognize bad block in memory. Then reliability of system gets reduced.
4) Usage of NOR and NAND memory: NOR is easy to use. Just connect it and use it. However, NAND not used like that. NAND has I/O interface and requires a driver for performing any operation. Read operation from NOR do not need any driver.