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Fujitsu MHV2040AH, MHV2100AH, MHV2060AH manual Start mode, Acceleration mode, Stable rotation mode

Models: MHV2040AH MHV2080AH MHV2060AH MHV2100AH

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4.7 Servo Control

4.7.5 Spindle motor control

Hall-less three-phase twelve-pole motor is used for the spindle motor, and the 3- phase full/half-wave analog current control circuit is used as the spindle motor driver (called SVC hereafter). The firmware operates on the MPU manufactured by Fujitsu. The spindle motor is controlled by sending several signals from the MPU to the SVC. There are three modes for the spindle control; start mode, acceleration mode, and stable rotation mode.

(1) Start mode

When power is supplied, the spindle motor is started in the following sequence:

a)After the power is turned on, the MPU sends a signal to the SVC to charge the charge pump capacitor of the SVC. The charged amount defines the current that flows in the spindle motor.

b)When the charge pump capacitor is charged enough, the MPU sets the SVC to the motor start mode. Then, a current (approx. 0.3 A) flows into the spindle motor.

c)A phase switching signal is generated and the phase of the current flowed in the motor is changed in the order of (V-phase to U-phase), (W-phase to U- phase), (W-phase to V-phase), (U-phase to V-phase), (U-phase to W-phase), and (V-phase to W-phase) (after that, repeating this order).

d)During phase switching, the spindle motor starts rotating in low speed, and generates a counter electromotive force. The SVC detects this counter electromotive force and reports to the MPU using a PHASE signal for speed detection.

e)The MPU is waiting for a PHASE signal. When no phase signal is sent for a specific period, the MPU resets the SVC and starts from the beginning. When a PHASE signal is sent, the SVC enters the acceleration mode.

(2) Acceleration mode

In this mode, the MPU stops to send the phase switching signal to the SVC. The SVC starts a phase switching by itself based on the counter electromotive force. Then, rotation of the spindle motor accelerates. The MPU calculates a rotational speed of the spindle motor based on the PHASE signal from the SVC, and waits till the rotational speed reaches 5,400 rpm. When the rotational speed reaches 5,400 rpm, the SVC enters the stable rotation mode.

(3) Stable rotation mode

The SVC builds the FLL/PLL circuit into, and to become the rotational speed of the target, controls a stable rotation with hardware.

The firmware calculates time of one rotation from PHASE signal. PHASE signal is outputted from the SVC. And the firmware observes an abnormal rotation.

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Fujitsu MHV2040AH, MHV2100AH, MHV2060AH, MHV2080AH manual Start mode, Acceleration mode, Stable rotation mode
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MHV2040AH, MHV2080AH, MHV2060AH, MHV2100AH specifications

The Fujitsu MHV series of hard disk drives, specifically the MHV2060AH, MHV2080AH, MHV2100AH, and MHV2040AH, are renowned for their reliability and performance in the mobile HDD segment. Designed primarily for use in laptops and other portable devices, these drives integrate cutting-edge technologies to meet the demands of today's data-intensive applications.

One of the hallmark features of the MHV series is its high data density, allowing for substantial storage capabilities in compact sizes. The MHV2060AH offers a storage capacity of 60 GB, while the MHV2080AH and MHV2100AH offer 80 GB and 100 GB respectively. The MHV2040AH provides a slightly more modest but still robust 40 GB of storage. This range of capacities ensures that users can select the model that best fits their storage needs.

The drives utilize the latest perpendicular magnetic recording (PMR) technology, which enhances recording efficiency and increases data storage densities. This technology significantly optimizes the use of disk surface area, providing better performance and more reliable data access. Additionally, the MHV series incorporates an advanced actuator system that ensures precision head positioning, enhancing data integrity and reducing error rates during read and write operations.

In terms of performance, the MHV series maintains a revolutions per minute (RPM) rating of 5400, which strikes a balance between speed and energy efficiency, making these drives suitable for low-power applications. The drives are also designed with a low acoustic level, generating minimal noise during operation—a crucial factor for mobile users who prefer quieter devices.

Furthermore, the Fujitsu MHV series features a robust shock resistance design, allowing them to withstand the rigors of mobile computing. This makes them suitable for use in portable environments subject to vibration and physical movement, thus ensuring data security and drive longevity.

Overall, the Fujitsu MHV2060AH, MHV2080AH, MHV2100AH, and MHV2040AH represent a formidable selection of mobile hard disk drives filled with advanced technologies and features, making them well-suited for a wide range of applications in today's fast-paced digital world. With their combination of storage capacity, performance, and durability, these drives continue to serve as reliable solutions for users seeking efficient data storage in portable formats.