Definition of:Microdrive

An ultra-miniature hard disk from Hitachi Global Systems. The Microdrive was introduced by IBM in 1998 and acquired by Hitachi in 2002. It contains a single disk platter the size of an American quarter that holds up to 8GB. Using one or two GMR heads, the entire mechanism is built into a Type II CompactFlash form factor.

Size Matters
The tiny elements inside such a small drive offer an advantage. Because the actuator has 50 times less inertia than one used in a larger drive, it can ramp up to full speed in half a second. As a result, the drive can stop spinning when data are not being accessed, which conserves power in handheld devices. See actuator and CompactFlash.

The Microdrive
A marvel of electromechanical technology, the Microdrive platter stops rotating to conserve power and can ramp up to full speed in half a second.