Seagate Video 3.5 HDD Product Manual, Rev. A
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2.7.1 Conducted noise
Input noise ripple is measured at the host system power supply across an equivalent 80-ohm resistive load on the +12 volt
line or an equivalent 15-ohm resistive load on the +5 volt line.
• Using 12-volt power, the drive is expected to operate with a maximum of 120 mV peak-to-peak square-wave injected
noise at up to 10MHz.
• Using 5-volt power, the drive is expected to operate with a maximum of
100 mV peak-to-peak square-wave injected
noise at up to 10MHz.
2.7.2 Voltage tolerance
Voltage tolerance (including noise):
• 5V ±5%
• 12V ±10%
2.7.3 Power-management modes
The drive provides programmable power management to provide greater energy efficiency. In most systems, users can
control power management through the system setup program. The drive features the following power-management
modes::
• Active mode
The drive is in Active mode during the read/write and seek operations.
• Idle mode
The electronics remain powered, and the drive accepts all commands and returns to Active mode when disk access
is necessary.
• Standby mode
The drive enters Standby mode immediately when the host sends a Standby Immediate command. If the host has
set the standby timer, the drive enters Standby mode automatically after the drive has been inactive for a specifi-
able length of time. The standby timer delay is established using a Standby or Idle command. In Standby mode, the
electronics are in low power mode, the heads are parked and the spindle is at rest. The drive accepts all commands
and returns to Active mode when disk access is necessary.
• Sleep mode
The drive enters Sleep mode after receiving a Sleep command from the host. In Sleep mode, the electronics are in low
power mode, the heads are parked and the spindle is at rest. The drive leaves Sleep mode after it receives a Hard Reset
or Soft Reset from the host. After receiving a reset, the drive exits Sleep mode and enters Standby mode.
• Idle and Standby timers
Each time the drive performs an Active function (read, write or seek), the standby timer is reinitialized and begins
counting down from its specified delay times to zero. If the standby timer reaches zero before any drive activity is
required, the drive makes a transition to Standby mode. In both Idle and Standby mode, the drive accepts all com-
mands and returns to Active mode when disk access is necessary.
Note
Equivalent resistance is calculated by dividing the nominal voltage by the typical RMS read/write current.
Power modes
Heads
Spindle
Electronics
Active
Tracking
Rotating
Full Power
Idle, Performance
Tracking
Rotating
Full Power
Idle, Active
Floating
Rotating
Partial Power
Idle, Low Power
Parked
Rotating
Partial Power
Standby
Parked Stopped
Low
Power
Sleep
Parked
Stopped
Low Power
