Initial Power Mode At Power On; Advanced Power Management (Able-3) Feature; Performance Idle Mode; Active Idle Mode - IBM IC25N020ATDA04 - Travelstar 20 GB Hard Drive Specifications

Though the interface is inactive in sleep mode, the access to the interface registers and the validity of
INTRQ is guaranteed for two seconds after the Sleep command is completed. After this period, the
contents of interface registers may be lost. Since the contents of interface registers may be invalid, the
host should NOT check the Status register nor the Alternate Status register prior to issuing a soft reset to
wake up a device.

11.5.7 Initial Power Mode at Power On

After power on or hard reset the device goes to IDLE mode or STANDBY mode depending on the option.
Refer to Part 1 of this document for the initial power mode selection.

11.6 Advanced Power Management (ABLE-3) 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.
This feature allows the host to select an advanced power management level. The advanced power
management level is a scale from the lowest power consumption setting of 01h to the maximum perfor-
mance 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:
Ÿ A SET FEATURES subcommand to enable Advanced Power Management
Ÿ 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 91,
bits 7-0 contain the current Advanced Power Management level if Advanced Power Management is
enabled.

11.6.1 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 described below.

11.6.2 Active Idle Mode

In this mode, power consumption is 45–55% less than that of Performance Idle mode. Additional
electronics are powered off, and the head is parked near the mid-diameter of the disk without servoing.
Recovery time to Active mode is about 20 ms.
Travelstar 48GH, 30GN & 15GN hard disk drive specifications
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