Construction

• CF cards use flash memory to store data. Flash memory is a solid-state memory technology, which means that a CF card contains no moving parts. Microdrives use magnetic disks to store data, much like a computer hard drive. Because the Microdrive contains moving parts, it is much more vulnerable to damage from sudden physical shock than is a solid-state CF card.
  
  

Power Consumption

• CF cards can operate at both 3.3V and 5V, which allows them to be interchanged between devices that operate at different voltage levels. Because they have no moving parts, CF cards use less power than Microdrives when attached to computers or portable devices. Devices that use CF cards demonstrate longer battery life and lower power consumption than devices that use Microdrives.
  
  

Storage Capacity

• The CompactFlash specification supports storage capacities of up to 137GB of data. CF cards typically come in sizes ranging from 1 to 16GB, though cards capable of storing up to 128GB of data can be purchased for consumer use. Microdrives are limited by magnetic disk technology and are typically available in sizes of 340MB to 6GB.
  
  

Interface

• Both the CF card and the Microdrive utilize a 50-pin connector to interface with electronic devices and come in two form factor specifications. The CompactFlash Type II specification is slightly thicker (5mm) than the CompactFlash Type I specification (3.3mm). Most CF cards meet the Type I specifications, though some are available in Type II specifications; all Microdrives fall into the Type II specification. Devices that meet the CompactFlash Type II specifications can interface with either the CF card or a Microdrive.
  
  

Usage

• CF cards are used in a variety of consumer devices, particularly digital cameras and portable media players. The CompactFlash specification makes the card ideal for devices that require a drive with low power consumption and high data capacity. Microdrives can be used in any device with a CompactFlash Type II interface and can be found in some portable media players and PocketPC computers.