SanDisk Homepage
 
Shop | Download | Support | Contact us
GO >
SanDisk Worldwide SanDisk Worldwide
Where To Buy
 
Product Background Information
 

Quick Jump:
CompactFlash -- An Industry Standard
Flash Technology
CompactFlash And The Digital Camera Market
Desktop Connectivity
MP3 Players, HPCs, Palm PCs, Auto PCs, Audio Recorders And  Photo  Printers

CompactFlash: Product/Applications Background Report

SanDisk Corporation's introduction of CompactFlash™ (CF™) in November, 1994, was a watershed event for the users of computers, cameras and consumer electronics products. CompactFlash technology has resulted in the introduction of a new class of advanced, small, lightweight, low-power mobile products that significantly increase the productivity and enhance the lifestyle of millions of people.

The concept behind CompactFlash, one of the world’s smallest, removable mass storage devices, is simple: to capture, retain and transport data, video, audio and images.

CompactFlash provides the capability to easily transfer all types of digital information and software between a large variety of digital systems including portable and desktop computers, handheld PCs (HPCs), personal communicators, Palm PCs, Auto PCs, digital cameras, digital voice recorders, photo printers and set-top boxes.

CompactFlash has set a new form factor standard for small, removable, high capacity, mass storage systems. It has found universal acceptance due to its compatibility with industry-standard functionality and electrical connectivity specifications established by the PCMCIA (Personal Computer Memory Card International Association). Data, audio and images on a CompactFlash memory card are transported to the PCMCIA-ATA (AT Bus Attachment) world of products via a standard PCMCIA Type II adapter card. The 50 pin CompactFlash card, about the size of a matchbook, slides easily into the adapter card. The adapter card has the standard 68 pin PCMCIA interface and can be inserted into any Type II or Type III PC Card ATA slot.

CompactFlash is the ideal storage solution for small form factor systems that need high capacity, removable mass storage with PCMCIA connectivity but are too small to accept a full-size PC Card. Product designers have been unable to develop many of those computing and communications systems thus far partly because no small removable storage device with sufficient capacity existed. CompactFlash is less than one-fourth the size (in volume) of a standard PCMCIA Type II PC card. It weighs approximately a half ounce and is 36 millimetres (1.4") long, 43 millimetres (1.7") wide and 3.3 millimetres (.13") thick. CompactFlash is available in capacities ranging from 8 to 512 Megabytes (MB).

Back to top

CompactFlash -- An Industry Standard
CompactFlash is manufactured and marketed by SanDisk and several other companies. SanDisk had made the specifications for CompactFlash, as well as the CompactFlash trademark (CF), available to other companies at no cost provided that they agree to support the CompactFlash specifications. SanDisk is confident that CompactFlash will become as popular as the CD ROM in the consumer electronics industry.

CompactFlash is based on flash memory semiconductor technology. Data, audio, video and images are stored on flash chips rather than the conventional, mechanical, rotating disk drives found in most computers. Flash is non-volatile memory, meaning that once data is saved on the card, it will be retained even if the system's power supply is switched off. Flash is also solid state and has no moving parts. Disk drives have many moving parts and are subject to mechanical problems. Flash is much more rugged and reliable and offers users considerably more protection of data. Mechanical disk drives found in portable computers typically have an operating shock rating of 100-200 Gs, which is equivalent to a drop of less than a foot. SanDisk’s CompactFlash has an operating shock rating of 2,000 Gs, equivalent to a 10-foot drop to the floor.

Flash is sometimes confused with SRAM (static random access memory) semiconductor storage technology. Flash is superior to SRAM in many respects. SRAM storage card typically have low capacities. SRAM requires a battery on board the card to retain data. If the battery expires or battery connections are disturbed with rough handling, the data is lost. Flash is considerably less expensive than SRAM.

Back to top

Flash Technology
SanDisk’s first CompactFlash cards, built in 1994, were originally based on 32Mbit flash chips built with SanDisk’s proprietary 0.5 micron technology. CompactFlash was the company's first product to use 32Mbit flash technology and a single chip integrated ATA controller. SanDisk’s CompactFlash cards include a controller that handles all the technology-dependent flash memory control algorithms. This integrated controller — which stores all IDE (Intelligent Drive Electronics) and ATA commands — makes CompactFlash fully compatible with all operating systems, utilities and application programs that support industry-standard IDE disk drives. Full BIOS and driver support for CompactFlash is already built into numerous platforms and operating systems because they currently support the identical PCMCIA-ATA standard. CompactFlash requires no special Flash File systems or drivers. All file management, error correction code, power management and PCMCIA controller I/O functionality is reduced to a single chip. CompactFlash operates on a single supply voltage of 3.3 or 5 volts. This gives CompactFlash the flexibility to work in systems that support only 3.3 volts or only 5 volts.

SanDisk expanded CompactFlash with 64Mbit technology in 1996, 128Mbit in 1998, 256Mbit in 1999 and 512Mbit in 2001. As the density of flash memory increases, considerably higher capacities can be achieved in the same size form factor. Costs also decrease and consumer prices decline as higher capacities can be obtained from the same number of silicon wafers. Demand for more storage always increases with time.

Back to top

CompactFlash And The Digital Camera Market
Market demand for CompactFlash has surged with the advent of new computers, cameras and electronics products. CompactFlash has widespread application in digital cameras. It is the "digital film" in small, lightweight digital cameras for the mass consumer market. Today, digital cameras generally cost between $199 and $999. With the availability of higher capacity memory cards, manufacturers of digital cameras have the option to increase the resolution quality of the already impressive digital camera quality. Some models require that the camera be tethered at all times to a PC so that the images, or photos, can be downloaded to the computer housing the digital storage device. Other models have embedded (non-removable) digital storage devices. Those users can't take any more pictures with their camera once the storage capacity is full until they can get to a computer and download the stored photos to the computer.

With CompactFlash, digital camera users are able to easily eject their "digital film" and transport the images via the PCMCIA Type II adapter card to either obtain prints or move the photos to another digital system such as a desktop computer, HPC, Palm PC, Auto PC or a photo printer. Photos can be "developed" in seconds and transmitted or printed using high resolution colour printers. Some copier outlets and other businesses already have colour printers equipped with PC Card slots. Panasonic offers a PC Card slot in one printer and Canon and Lexmark have CompactFlash slots in others. Camera buffs will be able to enhance the photos on their PCs before getting prints or uploading to FTP Internet sites.

Back to top

Desktop Connectivity
With SanDisk's 1998 introduction of ImageMate™, a fast, low-cost and easy-to-use external CompactFlash drive, pictures captured on digital cameras using CompactFlash can be downloaded directly from CompactFlash cards by inserting the card into the ImageMate where it then appears as another drive on the user's desktop PC or MAC. The USB ImageMate offers a transfer-rate that is up to 50 times faster than the serial port (on the camera) connection method. The ImageMate offers two connectivity solutions. One, via the PC's parallel port (with printer pass-through) and the other via Universal Serial Bus (USB) connection for all new PC and Apple MAC computers. Once the transfer is complete, the CompactFlash card can be erased and the consumer can continue taking more pictures.

Digital camera owners are using CompactFlash in a variety of ways. Estate agents take pictures of new homes that have just come on the market and put them instantly on the Internet or send them via email to prospective out-of-town buyers who will look at pictures of the homes on their computers. Insurance companies take pictures of accident scenes, cut and paste the pictures into accident reports they fill out on their computers and then submit the reports for processing and payment. People take pictures of family celebrations and within minutes send those photos electronically to relatives or friends in distant towns, cities or countries. Camera users no longer need to "waste" the shots at the end of a roll of 35MM film just to get pictures developed. They use as much or as little of the CompactFlash card as they need and then erase the CompactFlash when they have prints in hand or have stored the images digitally in their PC. The CompactFlash card is then free for more photo-taking.

Back to top

MP3 Players, HPCs, Palm PCs, Auto PCs, Audio Recorders And Photo Printers
CompactFlash provides a solution to a problem facing manufacturers of HPCs, Palm PCs, Auto PCs and personal communicators. The host devices now provide users with systems having two standard size PC card slots — one slot for a communications card and the other for a mass storage card. CompactFlash has solved the problem of limited space inside today's HPCs. One slot houses a PC card which can be used as the higher capacity slot. The other can be used with a CompactFlash card inside a PC Card Adapter. By using the CompactFlash card, manufacturers will have the ability to design smaller HPC and personal communication devices. Many HPC devices have also added the functionality to act as a portable MP3 music player. By using CompactFlash as the music storage device, consumers can store about a minute of near-CD quality MP3 compressed audio per megabyte. A 64MB CompactFlash card, for example, can easily store about an hour of MP3 compressed audio for playback.

Small, handheld audio recorders also employ CompactFlash technology. Audio messages are stored on CompactFlash cards capable of holding up to 30 minutes of voice per every 2MB of memory. With the PCMCIA adapter card or SanDisk's ImageMate, the digital messages can be moved to several different kinds of platforms. An office supervisor on the way to work could dictate a message to a subordinate who recently submitted an updated budget on a spreadsheet. The supervisor could note to the subordinate several areas on the spreadsheet where data seems inconsistent. Later, at the office, the spreadsheet user slips the CompactFlash into a PC and works on the document while being guided by the supervisor’s voice message which is annotated to the spreadsheet file.

Photo printers have entered the digital imaging market as well. Specific slots for CompactFlash memory cards have been designed into digital printers. This enables the end user of a digital camera using CompactFlash to eject the CompactFlash card, insert the card into the printer, and the printer then prints those stored images on special photo quality paper.

CompactFlash cards acquired for today’s new HPCs, Palm PCs, Auto PCs, communicators, voice recorders and other mobile systems also will function in advanced versions of those products when they are introduced. There is complete interoperability and cross platform capability with guaranteed forwards and backwards compatibility. In the future, for example, a mobile system owner who has been using a lower capacity CompactFlash based on 32Mbit, 64Mbit, 128Mbit or 256Mbit technology can add a new higher capacity card based on 512Mbit flash and it will work seamlessly. If the consumer keeps the mobile system for a number of years and later buys another CompactFlash based on more advanced flash technology, the new card will be compatible in the system.

Back to top