Theory of Device Operation

4.7 Servo Control

The actuator motor and the spindle motor are submitted to servo control. The actuator motor is controlled for moving and positioning the head to the track containing the desired data. To turn the disk at a constant velocity, the actuator motor is controlled according to the servo data that is written on the data side beforehand.

4.7.1 Servo control circuit

Figure 4.6 is the block diagram of the servo control circuit. The following describes the functions of the blocks:

(3)(4)

(7)

(5)(6)

Figure 4.6 Block diagram of servo control circuit

(1) Microprocessor unit (MPU)

The MPU includes the DSP unit, and the MPU starts the spindle motor, moves the heads to the reference cylinders, seeks the specified cylinder, and executes calibration according to the internal operations of the MPU. Main internal operation of the MPU are shown below.

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Fujitsu MHD2032AT, MHC2032AT, MHD2021AT, MHC2040AT manual Servo Control, Servo control circuit
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MHC2040AT, MHC2032AT, MHD2032AT, MHD2021AT specifications

Fujitsu offers a range of advanced hard disk drives (HDD) designed for various computing needs, including the MHD2021AT, MHD2032AT, MHC2032AT, and MHC2040AT models. These drives combine reliable performance, capacity options, and technological features aimed at enhancing data storage efficiency.

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