mechanical is nature than the stepper motors used in most small hard drives. The single voice coil dithers (or oscillates), thus moving in highly precise positionings. The intricacies of moving the permanent magnet—and, therefore, the arm/heads— are handled by a more sophisticated use of micro0 electronics...and simpler, more controllable use of electromagnetism as compared to the stepper.
Voice coil technology is certainly not new. All the large mass storage drives (80MB and up) use it on 5.25" full-sized drives. But Conner is the first to use voice coil in a 3.5", half-heighth environment— thanks to the work of John Squires, one of Conner's research and development geniuses. Squires reduc- ed the technology of voice coil actuation to propri- etary microcode rather than microelectronics.
(This is the stuff large scale technological advances are made of: he turned a board into chip.)
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Squires and the rest of Conner's Longmont, CO, research and development center also used a "closed loop embedded servo" to make more reliable read/writes once the data was accessed. With dedicated or embedded servos, each and every track written is verified. Drives using stepper technology don't usually verify a write to this extent. The very last step of the write verification is left undone, leaving an open loop. With a closed loop dedicated servo, one side of a platter in a hard drive is dedicated to the verifying of data—another reason that only the very largest drives have the space available to use voice activation with it's characteristic closed loop servo.
Conner can make a small drive (3.5", two platter) with voice coil activation because they use their OWN closed loop servo scheme. It's called "embed- ded servo." Instead of dedicating a single platter side to the read/write verification task, it simply
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