Flash memory is a type of non-volatile memory that can be electronically erased and reprogrammed. Its name was invented by Toshiba to express how much faster it could be erased - 'in a flash; which means 'very quickly' 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. Quoted from
Flash-based gadgets:
Flash memory is used in many hand held devices. See the pictures and their description.
a. This wireless LAN card allows laptop and PDA users to access the Internet from any Wi-Fi access point.
b. This flash-based player provides everything you need to play music and store data on the go. It also comes with a built-in FM radio and voice recorder.
c. It looks like an ordinary watch, but this USB drive from Edge Tech can store up to 1 GB of flash memory. It will let you save and transfer your photos, songs and data files easily.
d. This flash memory card is used as 'digital film' to store images on a digital camera.
e. This hand held console lets you play games stored on ROM game cards, which have a small amount of flash memory to save user data, for example high scores.
f. This USB flash pen drive is the latest mobile drive for your computer.
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