By Jason S Mills
SD, or Secure Digital, is a brand of memory cards that has largely taken over the flash memory market in devices like digital cameras and camcorders, laptops, Personal Digital Assistants, and even video game consoles. Its success can be measures throughout the years by its market penetration, adaptability to different types of devices, and its continuous effort to improve its ratings and write speeds.
SD, or Secure Digital, is a brand of memory cards that has largely taken over the flash memory market in devices like digital cameras and camcorders, laptops, Personal Digital Assistants, and even video game consoles. Its success can be measures throughout the years by its market penetration, adaptability to different types of devices, and its continuous effort to improve its ratings and write speeds.
Before SD memory cards went into production, Sandisk - one of the developers behind the Secure Digital format - pioneered the MultiMediaCard flash memory format. In conjunction with Siemens, Sandisk unveiled the MMC in 1997, so it goes without saying that they already had some experience under their belt when they wanted to create this newer format that would be slimmer, be capable of holding more data, and offer better R&W speeds.
Sandisk now makes SD memory cards in cooperation with Toshiba and Panasonic. Originally, they set out to rival Sony's already-established Memory Stick. This new, non-volatile, high density format was designed to fit in a tiny package: just 24 x 32 x 2.1mm. Although physically smaller than the memory stick, they knew that they needed a competitive edge to overcome Sony's reputation as the leading memory card format. Starting in 2000, Toshiba and Panasonic garnered a base of over 20 companies that would back this new SD advent.
Today, this group called the SD Association "is a global alliance of more than 1,000 companies involved in the design, development, manufacture or sale of products using SD technology" according to sdcard.org. The SDHC is another type of SD format that uses more sophisticated data densities, allowing you to store up to 64GB of information on a single chip! Since its establishment, much progress was made, and developments of smaller flash media products like the MiniSD and MicroSD formats have further solidified SD's stance as the dominating memory card format.
SD memory cards are based on FAT or FAT32 file systems, but can also be used with FAT16 file systems. They're sold by brands like Ativa, SanDisk, Lexar, Kodak, and ACP-EP. Transferring files from an SD card to your computer is easy. You can either do it by connecting your using device to the PC through a USB port, or you can take the actual SD memory chip out and copy files using a card reader.
Card readers are USB devices that allow you to move data from flash memory units. Also, new advanced cell phones let you take pictures and songs and other files from your SD memory card and send them to your email, or upload them to Facebook - all right at your fingertips. The format offers three file transfer types: one-bit, four-bit, and SPI modes; all SD, but not all MicroSD cards have to support all three of these transfer modes.
One disadvantage that the SD cards have is their lack of support of ATA signaling, which is supported by CompactFlash - one of the format's competitors. Another problem that the SD format faces is the counterfeit products that are openly sold on the Internet. These fakes harm the original brand's name, and offer less-than-advertised read & write speeds.
The future calls for innovative ways to read, write and store data, and no one knows how companies will embrace this consumer demand in the upcoming years. However, although SD memory cards are portable and offer a lot of space, it's unlikely that new technologies will beat small USB flash drives, which were available in capacities up to 256GB, and were around since 2001.
Article Written By: Jason Mills, Techdna.co.uk
Article Source: http://news.techdna.co.uk/2010/01/sd-memory-cards/
Article Source: http://EzineArticles.com/?expert=Jason_S_Mills
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