Flash Memory Buying Guide

Flash memory is used in flash drives and derives its name from the electronic process of flashing a ‘cell’ within the memory chip in order to clear or change the data stored there. Flash memory is non-volatile computer memory that can be electrically erased and reprogrammed many times. It is non-volatile, which means that it does not need power to maintain the information stored in the chip. Flash memory is used in digital cellular phones, digital cameras, LAN switches, secondary computer storage, digital set-up boxes, embedded controllers, and other electronic devices. It is also very useful in a variety of applications including: computer BIOS Memory chips, PCMCIA memory cards, MP3 players, modems, and video game consoles.

Capacity

The largest capacity in flash memory is currently 64 GB. The capacity of electronic memory has steadily increased over the years, tracking with Moore's Law, which predicts that the numbers of transistors on a chip will double every two years. 1 GB capacity flash memory has become the normal storage space for people who do not extensively use flash memory, while more and more consumers are adopting 2 GB or 4 GB flash drives. Rapid increases in the capacity of NAND flash, coupled with mobile consumer products that demand ever-increasing amounts of data storage, lay out a very bright future for this technology in the coming years.

Speed

Flash memory cards are available in different speeds. Flash memory product manufacturers provide “x-speed” ratings for flash cards similar to that used by optical drives. For example a speed of 1X is 150 KB/s, i.e. 150 kilobytes per second, and therefore a rating of 10X should be a transfer speed of 1500 KB/s (1.5MB/s). Inserting a USB 2.0 Flash drive on a computer that supports only the slower USB 1.0 speeds (12 MB/s) will not result in faster transfers. Flash card storage device performance depends on the following three factors: The specific Flash memory chips used: Generally, there is a tradeoff between the high-speed and more expensive Single-Level Cell (SLC) Flash chips, and the standard speed and more affordable Multi-Level Cell (MLC) or Multi-Bit Cell (MBC) Flash chips.

Card Types

Here are the most popular formats for flash memory currently in use.

SD- Secure Digital is a ubiquitous flash memory card used in a variety of applications especially digital cameras.

MiniSD- Smaller than the standard SD card MiniSD is used in applications where small size is important, i.e., cell phones and MP3 players.

MicroSD-Very small flash memory used in ultra-fashionable cell phones, etc.

MMC- Multimedia cards used extensively in digital devices.

RS-MMC-Reduced size MMC card

MMCplus-MMC media card that complies with MMC4.0 spec and is the same size as the regular MMC card , but is faster

MMCmobile-same size and spec of RS-MMC but capable of faster transfer speeds

CF I- Compact Flash is an early type of flash card.

CF-II-Compact flash that offers large storage capacities over CF-I.

MS-memory stick-Sony proprietary flash. Large size and obsolete.

MS PRO-Sony proprietary flash with transfer rate of up to 160Mbps. With 4 GB storage.

MS DUO-Half the size of the Sony MS flash primarily used in ultra small digital devices.

MS PRO DUO-MS PROs tech specs and the size of MS DUO.Using an adapter makes it compatible with MS PRO media

MS Micro–Sony memory stick micro aka M2. Fingernail size card. With adapter compatible with MS PRO products.

SM- Smart Media is older flash replaced with XD technology

XD-flash tech used primarily by Fuji and Olympus cameras.

With so many formats available, the key to choosing the right one is to determine the format(s) supported by your digital device prior to purchase. To be doubly sure of your choice, check with the manufacturer’s website and/or the product manual as well.

Card Readers

While most digital cameras can be hooked up to a computer to download pictures, sometimes it is more convenient to remove the flash card from the camera and read directly off of it to download pictures. This is accomplished by using a card reader attached to your computer. Most card readers can accept the majority of the competing flash cards. Some readers are limited to a few flash formats. The reader can either be external or internal to the computer. They are inexpensive and very handy, especially for mobile users. For the fastest transfer speeds (if you bought a high speed flash card) make sure the card reader uses the USB 2.0 interface.

Conclusion

Flash memory is more reliable than hard drives and can store more information in a smaller space, which will allow notebook makers to reduce the size of their computers. Flash memory is nearly indestructible by physical means & is able to withstand intense pressure and boiling water. By 2007, flash memory is expected to be a $43 billion industry. A lot of people in the industry believe that flash memory is the future of data storage for personal computers. The concept is simple: hard drives require a motor to physically move a read/write head, while flash memory is a solid state device that offers random access. Take a look at a great selection of flash memory cards here.