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
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
Additional details
Upon system power up, PHY communication is initiated with a COMRESET signal, which is generated by the
For more details, refer to:
•Section 6.8 of the Serial ATA 1.0
•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 Product Manual, Rev. C | 9 |
