Compact Flash Memory Cards

The size of the Compact Flash card is 42.8mm x 36.4mm x 3.3mm - the volume of the Compact Flash card is less than a quarter of the volume of the PCMCIA card. Although it only has 50 pins, the Compact Flash card is fully PCMCIA ATA compliant (a typical PCMCIA card has 68 pins). This means that to adapt the Compact Flash card to work with a PCMCIA slot, all you need is a passive adapter with a 68-pin output. The given size refers to Compact Flash type I cards - there are also Compact Flash type II cards, with a slightly higher thickness - up to 5mm; a good example of a Compact Flash type II device is the IBM MicroDrive - a small disk drive with a capacity of up to a few GB.

Compact Flash memory cards use memory made (as the name suggests) in flash technology - this means that this memory is "non-volatile" - data is stored for any length of time without the need to use any additional power supply. Compact Flash memory cards do not contain moving parts - thus providing much better protection of stored data than typical magnetic media (especially all types of disks and floppy disks). Compact Flash cards are rated to be five to ten times more reliable than typical drives used in mobile equipment. In addition, a working Compact Flash card consumes about 95% less power than an analogous disk drive. Compact Flash cards provide data transfer rates of up to 160MB/s.

Since the Compact Flash standard is compatible with the PCMCIA standard, other peripherals in the Compact Flash format are also available in addition to memory - I/O cards, modems, network cards, USB controllers, laser scanners, BlueTooth and 802.11b WiFi LAN cards, etc. Cards containing devices of this type often have an "extended" casing.

Unlike other small storage media, Compact Flash cards work with both 3.3V and 5V voltages - this means that each card can be freely used in both 3.3V and 5V devices. This makes CF cards ideal for a very wide range of mobile devices.

Compact Flash cards, while remaining compliant with the PCMCIA standard in this field, offer the most reliable (among media of this size) connector, perfectly tolerating frequent manipulation (inserting and removing the card from the devices in which it is used).
Compact Flash cards are designed to withstand a shock of up to 2000 G (equivalent to a drop from a height of more than three meters) without damage. Under typical operating conditions, CF cards provide completely error-free data storage for at least 100 years.
Due to their PCMCIA-ATA compatibility, CF cards are compatible with the vast majority of operating systems - DOS, Windows, OS/2, Apple System 7 and above, most types of UNIX, and many others. All of these systems work not only with CF memory cards, but also with CF memory drives and other peripherals.

Compact Flash memory cards have (unlike e.g. SmartMedia cards) a built-in memory controller - containing mechanisms for error correction, detection and bypassing of possible memory defects. Records on CF memory cards are usually organized in the FAT16 standard - some, especially older, devices using CF memory cards may not read cards formatted in the FAT32 standard!

A novelty on the market are Compact Flash type III cards, in which the read and write speed has been significantly increased.