Datasheet

12.7 Advanced Power Management Feature
This feature provides power saving without performance degradation. The Adaptive Battery Life
Extender 3 (ABLE-3) technology intelligently manages transition among power modes within the device
by monitoring access patterns of the host.
This technology has three idle modes: Performance Idle mode, Active Idle mode, and Low Power Idle
mode. The drive supports Performance Idle mode and Low Power Idle mode.
This feature allows the host to select an advanced power management level. The advanced power man-
agement level is a scale from the lowest power consumption setting of 01h to the maximum performance
level of FEh. Device performance may increase with increasing advanced power management levels.
Device power consumption may increase with increasing advanced power management levels. The
advanced power management levels contain discrete bands, described in the section of SET FEATURE
command in detail.
This feature set uses the following functions:
y A SET FEATURES subcommand to enable Advanced Power Management
y A SET FEATURES subcommand to disable Advanced Power Management
The Advanced Power Management feature is independent of the Standby timer setting. If both Advanced
Power Management level and the Standby timer are set, the device will go to the Standby state when the
timer times out or the device's Advanced Power Management algorithm indicates that it is time to enter
the Standby state.
The IDENTIFY DEVICE response word 83, bit 3 indicates that Advanced Power Management feature is
supported if set. Word 86, bit 3 indicates that Advanced Power Management is enabled if set.
Word 96, bits 7-0 contain the current Advanced Power Management level if Advanced Power
Management is enabled.
12.7.1 Performance Idle mode
This mode is usually entered immediately after Active mode command processing is complete instead of
conventional idle mode. In Performance Idle mode, all electronic components remain powered and full
frequency servo remains operational. This provides instantaneous response to the next command. The
duration of this mode is intelligently managed as the following describes.
12.7.2 Low Power Idle mode
Power consumption is 55–65% less than that of Performance Idle mode. The heads are unloaded onto
the ramp. The spindle is still rotated at the full speed. Recovery time to the Active mode is about 300 ms.
12.7.3 Transition Time
The transition time is dynamically managed by the user's recent access pattern instead of using fixed
access times. The ABLE-3 algorithm monitors the interval between commands instead of the command
frequency of ABLE-2. The algorithm supposes that next command will come with the same command
interval distribution as the previous access pattern. The algorithm calculates the expected average saving
energy and response delay for next command in several transition time case based on this assumption.
And it selects the most effective transition time with the condition that the calculated response delay is
Hard disk drive specification for DSCM-11000/-10512/-10340
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