Figure 2. Typical +5V only startup and operation current profile

2.9.2Deferred spinup

Momentus 5400.2 SATA drives provide a deferred spinup feature which storage subsystem controllers can use to sequence disc drive initialization. This is beneficial to systems which include multiple Serial ATA hard disc drives because it allows subsystem controllers to stagger the spinup of each drive to accommodate available power supply current. This feature does not impact time-to-ready in typical desktop systems.

To accommodate the deferred spinup of multiple disc drives in an enclosure, Momentus 5400.2 SATA disc drives will spin up only after power is applied to the drive and after successful PHY (Physical layer) initializa- tion. PHY initialization occurs after the PHY enters the DP7:DR_Ready state. This state is reached after a suc- cessful exchange of Out-Of-Band (OOB) signals with a functional host-side Serial ATA port. In desktop systems, SATA transceivers should initialize OOB as soon as power comes ready to guarantee the drive spins up quickly. Seagate disc drives will not spin up without an operational host-side Serial ATA transceiver.

Additional details

Upon system power up, PHY communication is initiated with a COMRESET signal, which is generated by the host-side transceiver. COMRESET is followed by a COMINIT signal generated by the disc drive transceiver. COMRESET and COMINIT are followed by an exchange of COMWAKE signals and Align primitives. The disc drive will spin up after the successful exchange of Align primitives cause the PHY to come ready.

For more details, refer to:

Section 6.8 of the Serial ATA 1.0 High-Speed Serialized AT Attachment specification

Section 6.2 of the Serial ATA II: Extensions to Serial ATA 1.0 specification

SATA 1.0 design guides

Note. These specifications and guides are available on the Serial ATA web site (www.serialata.org).

Momentus 5400.2 SATA Blade Server Product Manual, Rev. B

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Seagate ST98823SB, ST96812SB, ST94813SB, ST9120821SB, ST9100824SB manual Deferred spinup, Additional details

ST96812SB, ST9100824SB, ST94813SB, ST9120821SB, ST98823SB specifications

The Seagate series of hard drives, including the ST98823SB, ST9120821SB, ST94813SB, ST9100824SB, and ST96812SB, have been pivotal in the evolution of data storage solutions. Each model features specific enhancements that cater to different storage needs, while still reflecting Seagate's commitment to quality and performance.

The ST98823SB is a high-capacity hard drive designed primarily for enterprise use. One of its key features is its 7200 RPM spindle speed, which ensures fast data access and transfer rates. This drive typically supports Ultra ATA/133 interface, which enhances its data transfer capabilities. The robust design and high MTBF (Mean Time Between Failures) rating of the ST98823SB make it a reliable option for critical applications and large data storage.

Moving on to the ST9120821SB, this model emphasizes storage efficiency and reliability. With a capacity of around 120GB, it is ideal for storing operating systems and essential applications. The ST9120821SB also boasts a 7200 RPM speed, ensuring quick load times. This drive often features advanced power management technologies, reducing energy consumption while maintaining high performance, making it suitable for both desktop and server environments.

The ST94813SB is designed with a balance between performance and capacity. It typically offers a 48GB storage solution, catering to users who require speed without needing extensive space. With its SATA interface and a rotational speed of 7200 RPM, this drive supports high-performance applications while ensuring data integrity and reliability.

The ST9100824SB enhances the user experience with its 2.5-inch form factor, making it suitable for laptops and portable devices. With storage capacities around 100GB, this drive is designed to be energy-efficient, reducing the overall power consumption of mobile devices. It also utilizes advanced caching algorithms for improved performance, particularly in read operations.

Lastly, the ST96812SB stands out for its robust architecture, designed to withstand the rigorous demands of industrial applications. With a spin speed of 7200 RPM and a SATA interface, this drive offers a commendable mixture of speed and durability. It is often used in environment-sensitive applications where reliability is crucial.

Together, these Seagate models represent a diverse range of storage solutions, each tailored to meet specific consumer demands while ensuring reliable performance and impressive technology features.