Overview of the Drives
Chapter 1
Technical Reference Manual
Page 5
Drive Motor and Spindle
A brushless DC direct-drive motor assembly is mounted on the drive’s base. The
motor rotates the drive’s spindle at 7200 RPM. The motor/spindle assembly is
dynamically balanced to provide minimal mechanical runout to the disks. A
dynamic brake is used to provide a fast stop to the spindle motor and return the
heads to the landing zone when power is removed.
Head Positioning Mechanism
The read/write heads are supported by a mechanism coupled to a rotary voice
coil actuator.
Read/Write Heads and Disks
Data is recorded on 95mm diameter disks through 3370-type 50% nano-slider
thin film heads with transverse pressure contour (TPC) air bearing surfaces.
The TPC air bearing surface allows the head to fly at a uniform height
regardless of radial position. This improves data reliability and allows the aerial
density to be more uniform with radius. The CFP4207 series contains ten
sputtered thin film disks with twenty data surfaces and twenty read/write
heads.
At power-down, the heads are automatically retracted to the inner diameter of
the disk and are latched and parked on a landing zone that is inside the data
tracks.
Data and Power Connections
Data and power connections to the drive are different between the drive models.
Refer to chapter 4 for information regarding a specific model's requirements.
Electrical Design Features
Integrated Circuit
A single integrated circuit (IC) is mounted within the sealed hard drive assembly
in close proximity to the read/write heads. The IC provides head selection, read
pre-amplification, and write drive circuitry.
Circuit Board
The drive’s dual-microprocessor-controlled circuit board provides the remaining
electronic functions, which include:
•
read/write circuitry
•
rotary actuator control
•
interface control
•
spin speed control
•
auto-park
•
power management