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Hitachi HDS723020BLA642 manual Preventive maintenance, Load/unload, Emergency unload

Models: HDS723020BLA642

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7K200 SATA OEM Specification

6.3.5Preventive maintenance

None.

6.3.6Load/unload

The product supports a minimum of 600,000 normal load/unloads.

Load/unload is a functional mechanism of the hard disk drive. It is controlled by the drive micro code. Specifically, unloading of the heads is invoked by the following commands:

Standby

Standby immediate Sleep

Load/unload is also invoked as one of the idle modes of the drive.

The specified start/stop life of the product assumes that load/unload is operated normally, not in emergency mode.

6.3.6.1Emergency unload

When hard disk drive power is interrupted while the heads are still loaded the micro code cannot operate and the normal 5-volt power is unavailable to unload the heads. In this case, normal unload is not possible. The heads are unloaded by routing the back EMF of the spinning motor to the voice coil. The actuator velocity is greater than the normal case and the unload process is inherently less controllable without a normal seek current profile.

Emergency unload is intended to be invoked in rare situations. Because this operation is inherently uncontrolled, it is more mechanically stressful than a normal unload.

The drive supports a minimum of 20,000 emergency unloads.

6.3.6.2Required Power-Off Sequence

The required host system sequence for removing power from the drive is as follows: Step 1: Issue one of the following commands.

Standby

Standby immediate Sleep

Note: Do not use the Flush Cache command for the power off sequence because this command does not invoke Unload.

Step 2: Wait until the Command Complete status is returned.

In a typical case 500 ms are required for the command to finish completion; however, the host system time out value needs to be 30 seconds considering error recovery time. Refer to section 15.0, "Time-out values," on page 172.

Step 3: Terminate power to HDD.

This power-down sequence should be followed for entry into any system power-down state, system suspend state, or system hibernation state. In a robustly designed system, emergency unload is limited to rare scenarios, such as battery removal during operation.

6.3.6.3Power switch design considerations

In systems that use the Travelstar 7K200 consideration should be given to the design of the system power switch.

Hitachi recommends that the switch operate under control of the BIOS, as opposed to being hardwired. The same recommendation is made for cover-close switches. When a hardwired switch is turned off,

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Hitachi HDS723020BLA642 manual Preventive maintenance, Load/unload, Emergency unload, Required Power-Off Sequence
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HDS723020BLA642 specifications

The Hitachi HDS723020BLA642 is a high-performance hard disk drive that exemplifies the balance between reliability and advanced technology, making it an excellent choice for a range of applications, from desktop computers to enterprise storage solutions. This 2TB SATA hard drive is designed to meet the growing data storage needs of users who demand both speed and efficiency.

One of the key features of the HDS723020BLA642 is its impressive rotational speed of 7200 RPM. This speed facilitates faster data access and improved overall performance, significantly enhancing the user experience during data-intensive operations such as gaming, video editing, and large file transfers. Coupled with a SATA III interface, this drive facilitates data transfer rates of up to 6 Gb/s, providing an efficient conduit for moving data quickly between the hard drive and the motherboard.

The drive comes equipped with a large 64 MB cache, which plays a crucial role in buffering read and write operations. This substantial amount of cache memory allows the drive to temporarily store frequently accessed data, leading to reduced latency and enabling smoother multitasking capabilities. Users will benefit from faster load times and reduced wait periods when working with large files.

Reliability is another defining characteristic of the HDS723020BLA642. Hitachi, now a part of Western Digital, has a longstanding reputation for producing durable hard drives. This model incorporates advanced technologies, such as the Fluid Dynamic Bearing (FDB) for quieter operation and better longevity. The drive also features an enhanced error recovery system that minimizes the risk of data loss, making it a suitable option for both personal and professional use.

In terms of power efficiency, the HDS723020BLA642 is designed to consume less power during operation compared to older hard drive models. This efficiency not only helps in reducing operational costs but also contributes to a longer lifespan for the drive itself.

Overall, the Hitachi HDS723020BLA642 hard drive combines speed, reliability, and efficiency into a compact package, making it an ideal choice for users needing a substantial amount of storage without compromising on performance. Whether for upgrading an existing system or building a new one, this drive offers a blend of technology and durability that caters to modern storage demands.